<html>
  <head>
    <title>
      CIPS, CILCORP, CILCO, IP 8-K, dated 06/07/2006
</title>
<!-- Licensed to: Ameren-->
<!-- Document Created using EDGARizer HTML 3.0.4.0 -->
<!-- Copyright 2006 EDGARfilings, Ltd., an IEC company.-->
<!-- All rights reserved EDGARfilings.com -->
</head>
  <body bgcolor="#ffffff"><br>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">UNITED
      STATES</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">SECURITIES
      AND EXCHANGE COMMISSION</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Washington,
      D.C. 20549</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center">&#160;

      <div>
        <hr style="COLOR: black" align="center" noshade size="2" width="13%">
      </div>
    </div>
    <div>
      <table cellpadding="0" cellspacing="0" width="100%">

          <tr>
            <td valign="top" width="72%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">FORM
                8-K</font></div>
            </td>
          </tr>

      </table>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CURRENT
      REPORT</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Pursuant
      to Section 13 or 15(d) of the</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Securities
      Exchange Act of 1934</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Date
      of
      report (Date of earliest event reported):</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><a name="ReportDate"/></div>
    <div>
      <table cellpadding="0" cellspacing="0" width="100%">

          <tr>
            <td valign="top" width="72%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">June
                7, 2006</font></div>
            </td>
          </tr>

      </table>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div>
      <table cellpadding="0" cellspacing="0" width="100%">

          <tr>
            <td align="left" valign="top" width="24%" style="border-bottom: #ffffff thin solid;">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>Commission
                File Number</u></font></div>
            </td>
            <td align="left" valign="top" width="24%" style="border-bottom: #ffffff thin solid;">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Exact
                Name of Registrant as Specified in Charter;</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">State
                of Incorporation;</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>Address
                and Telephone Number</u></font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
            <td align="left" valign="top" width="25%" style="border-bottom: #ffffff thin solid;">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">IRS
                Employer</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>Identification
                Number</u></font></div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">1-3672</font></div>
            </td>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Central
                Illinois Public Service Company</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Illinois
                Corporation)</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">607
                East Adams Street</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Springfield,
                Illinois 62739</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(217)
                523-3600</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
            <td align="left" valign="top" width="25%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">37-</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">0211380</font></div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">2-95569</font></div>
            </td>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCORP
                Inc.</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Illinois
                Corporation)</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">300
                Liberty Street</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Peoria,
                Illinois 61602</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(309)
                677-5271</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
            <td align="left" valign="top" width="25%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">37-1169387</font></div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">1-2732</font></div>
            </td>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Central
                Illinois Light Company</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Illinois
                Corporation)</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">300
                Liberty Street</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Peoria,
                Illinois 61602</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(309)
                677-5271</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
            <td align="left" valign="top" width="25%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">37-0211050</font></div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">1-3004</font></div>
            </td>
            <td align="left" valign="top" width="24%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Illinois
                Power Company</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Illinois
                Corporation)</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">370
                South Main Street </font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Decatur,
                Illinois 62523</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(217)
                424-6600</font></div>
            </td>
            <td align="left" valign="top" width="25%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">37-0344645</font></div>
            </td>
          </tr>

      </table>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><a name="Address"/><a name="Zip"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Check
      the
      appropriate box below if the Form 8-K filing is intended to simultaneously
      satisfy the filing obligation of the registrant under any of the following
      provisions:</font></a></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">[
&#160;]
      Written communications pursuant to Rule 425 under the Securities Act (17 CFR
      230.425)</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">[&#160;
]
      Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
      240.14a-12)</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: -4.5pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">[
&#160;]
      Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange
      Act
      (17 CFR 240.14d-2(b))</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">[
      ]
      Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange
      Act
      (17 CFR 240.13e-4(c))</font></div>
    <div>&#160;</div>
    <div id="PGBRK" style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt">
      <div id="FTR">
        <div id="GLFTR" style="WIDTH: 100%" align="left">
        </div>
      </div>
      <div id="PN" style="PAGE-BREAK-AFTER: always">
        <div style="WIDTH: 100%; TEXT-ALIGN: center">
        </div>
        <div style="WIDTH: 100%; TEXT-ALIGN: center">
          <hr style="COLOR: black" noshade size="2">
        </div>
      </div>
      <div id="HDR">
        <div id="GLHDR" style="WIDTH: 100%" align="right">
        </div>
      </div>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">ITEM
      8.01
      Other Events.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Central
      Illinois Public Service Company, doing business as AmerenCIPS (&#8220;CIPS&#8221;), Central
      Illinois Light Company, doing business as AmerenCILCO (&#8220;CILCO&#8221;), and Illinois
      Power Company, doing business as AmerenIP (&#8220;IP&#8221;), each hereby file their
      Statement of Computation of Ratio of Earnings to Fixed Charges and Combined
      Fixed Charges and Preferred Stock Dividend Requirements for the three months
      ended March 31, 2006. CILCORP Inc. (&#8220;CILCORP&#8221;) hereby files its Statement of
      Computation of Ratio of Earnings to Fixed Charges for the three months ended
      March 31, 2006.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">ITEM
      9.01
      Financial Statements and Exhibits.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(d)
      Exhibits</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div>
      <table cellpadding="0" cellspacing="0" width="100%">

          <tr>
            <td align="left" valign="top" width="13%" style="border-bottom: #ffffff thin solid;">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Exhibit</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>Number</u></font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">:</font></div>
            </td>
            <td align="left" valign="top" width="15%">&#160;</td>
            <td align="left" valign="bottom" width="46%" style="border-bottom: #ffffff thin solid;">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>Title</u></font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">:</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font></div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.1</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CIPS</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CIPS&#8217;
                Statement of Computation of Ratio of Earnings to Fixed </font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Charges
                and Combined Fixed </font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Charges
                and Preferred Stock</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Dividend
                Requirements</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.2</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCORP</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCORP&#8217;s
                Statement of Computation of Ratio of Earnings to</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Fixed
                Charges </font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.3</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCO</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCO&#8217;s
                Statement of Computation of Ratio of Earnings to Fixed</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Charges
                and Combined Fixed Charges and Preferred Stock</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Dividend
                Requirements</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.4
                </font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">IP</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">IP&#8217;s
                Statement of Computation of Ratio of Earnings to Fixed</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Charges
                and Combined Fixed Charges and Preferred Stock</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Dividend
                Requirements</font></div>
            </td>
          </tr>

      </table>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">____________</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">This
      combined Form 8-K is being filed separately by Central Illinois Public Service
      Company, CILCORP Inc., Central Illinois Light Company and Illinois Power Company
      (each a &#8220;registrant&#8221;). Information contained herein relating to any individual
      registrant has been filed by such registrant on its own behalf. No registrant
      makes any representation as to information relating to any other
      registrant.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div id="PGBRK" style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt">
      <div id="FTR">
        <div id="GLFTR" style="WIDTH: 100%" align="left">
        </div>
      </div>
      <div id="PN" style="PAGE-BREAK-AFTER: always">
        <div style="WIDTH: 100%; TEXT-ALIGN: center"><font style="DISPLAY: inline; FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">2</font></div>
        <div style="WIDTH: 100%; TEXT-ALIGN: center">
          <hr style="COLOR: black" noshade size="2">
        </div>
      </div>
      <div id="HDR">
        <div id="GLHDR" style="WIDTH: 100%" align="right">
        </div>
      </div>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 297pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">SIGNATURES</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 27pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Pursuant
      to the requirements of the Securities Exchange Act of 1934, each registrant
      has
      duly caused this report to be signed on its behalf by the undersigned thereunto
      duly authorized. The signature for each undersigned company shall be deemed
      to
      relate only to matters having reference to such company or its
      subsidiaries.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 207pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 297pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CENTRAL
      ILLINOIS PUBLIC SERVICE COMPANY</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 297pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Registrant)</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 36pt; TEXT-INDENT: 261pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>/s/
      Jerre E.
      Birdsong&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;
</u></font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 297pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Name:
      Jerre E. Birdsong</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 297pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Title:
      Vice President and Treasurer</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCORP
      Inc.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Registrant)</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>/s/
      Jerre E.
      Birdsong&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;
</u></font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Name:
      Jerre E. Birdsong</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Title:
      Vice President and Treasurer</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CENTRAL
      ILLINOIS LIGHT COMPANY</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Registrant)</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>/s/
      Jerre E.
      Birdsong&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;
&#160;</u></font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Name:
      Jerre E. Birdsong</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Title:
      Vice President and Treasurer</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">ILLINOIS
      POWER COMPANY</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(Registrant)</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>/s/
      Jerre E.
      Birdsong&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;
</u>&#160;</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Name:
      Jerre E. Birdsong</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 180pt; TEXT-INDENT: 117pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Title:
      Vice President and Treasurer</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 207pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 27pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Date:
      June 7, 2006</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br>&#160;</div>
    <div id="PGBRK" style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt">
      <div id="FTR">
        <div id="GLFTR" style="WIDTH: 100%" align="left">
        </div>
      </div>
      <div id="PN" style="PAGE-BREAK-AFTER: always">
        <div style="WIDTH: 100%; TEXT-ALIGN: center"><font style="DISPLAY: inline; FONT-SIZE: 8pt; FONT-FAMILY: Times New Roman">3</font></div>
        <div style="WIDTH: 100%; TEXT-ALIGN: center">
          <hr style="COLOR: black" noshade size="2">
        </div>
      </div>
      <div id="HDR">
        <div id="GLHDR" style="WIDTH: 100%" align="right">
        </div>
      </div>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">EXHIBIT
      INDEX</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><br></div>
    <div>
      <table cellpadding="0" cellspacing="0" width="100%">

          <tr>
            <td align="left" valign="bottom" width="13%" style="border-bottom: #ffffff thin solid;">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Exhibit</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>Number</u></font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">:</font></div>
            </td>
            <td align="left" valign="top" width="15%">&#160;</td>
            <td align="left" valign="top" width="46%" style="border-bottom: #ffffff thin solid;">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><u>Title</u></font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">:</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font></div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.1</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CIPS</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CIPS&#8217;
                Statement of Computation of Ratio of Earnings to Fixed </font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Charges
                and Combined Fixed Charges and Preferred Stock</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Dividend
                Requirements</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.2</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCORP</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCORP&#8217;s
                Statement of Computation of Ratio of Earnings to</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Fixed
                Charges </font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">&#160;</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.3</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCO</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">CILCO&#8217;s
                Statement of Computation of Ratio of Earnings to</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Fixed
                Charges and Combined Fixed Charges and Preferred Stock </font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Dividend
                Requirements</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
            </td>
          </tr>
          <tr>
            <td align="left" valign="top" width="13%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">12.4
                </font><font id="TAB2" style="COLOR: black; LETTER-SPACING: 27pt">&#160;</font></div>
            </td>
            <td align="left" valign="top" width="15%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">IP</font></div>
            </td>
            <td align="left" valign="top" width="46%">
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">IP&#8217;s
                Statement of Computation of Ratio of Earnings to Fixed</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Charges
                and Combined Fixed Charges and Preferred Stock</font></div>
              <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Dividend
                Requirements</font></div>
            </td>
          </tr>

      </table>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left"><br>&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="left">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">4</font></div>
  </body>
</html>
[{"type": "8-K", "sequence": "1", "filename": "form8k06072006.htm", "description": "CIPS, CILCORP, CILCO, IP 8-K, DATED 06/07/2006", "secsgml_size_bytes": 51004}]
[{"company-data": {"conformed-name": "CENTRAL ILLINOIS LIGHT CO", "cik": "0000018651", "assigned-sic": "4931", "irs-number": "370211050", "state-of-incorporation": "IL", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-02732", "film-number": "06890581"}, "business-address": {"street1": "300 LIBERTY ST", "city": "PEORIA", "state": "IL", "zip": "61602", "phone": "309-677-5230"}, "mail-address": {"street1": "300 LIBERTY STREET", "city": "PEORIA", "state": "IL", "zip": "61602"}}, {"company-data": {"conformed-name": "CENTRAL ILLINOIS PUBLIC SERVICE CO", "cik": "0000018654", "assigned-sic": "4931", "irs-number": "370211380", "state-of-incorporation": "IL", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-03672", "film-number": "06890579"}, "business-address": {"street1": "607 E ADAMS ST", "city": "SPRINGFIELD", "state": "IL", "zip": "62739", "phone": "217-523-3600"}, "mail-address": {"street1": "CENTRAL ILLINOIS PUBLIC SERVICE CO", "street2": "607 E ADAMS ST", "city": "SPRINGFIELD", "state": "IL", "zip": "62739"}}, {"company-data": {"conformed-name": "ILLINOIS POWER CO", "cik": "0000049816", "assigned-sic": "4931", "irs-number": "370344645", "state-of-incorporation": "IL", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-03004", "film-number": "06890580"}, "business-address": {"street1": "500 S 27TH ST", "street2": "C/O HARRIS TRUST & SAVINGS BANK", "city": "DECATUR", "state": "IL", "zip": "62525-1805", "phone": "2174246600"}, "mail-address": {"street1": "500 SOUTH 27TH STREET", "city": "DECATUR", "state": "IL", "zip": "62521"}, "former-company": {"former-conformed-name": "ILLINOIS IOWA POWER CO", "date-changed": "19660822"}}, {"company-data": {"conformed-name": "CILCORP INC", "cik": "0000762129", "assigned-sic": "4931", "irs-number": "371169387", "state-of-incorporation": "IL", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "002-95569", "film-number": "06890582"}, "business-address": {"street1": "300 LIBERTY ST", "street2": "STE 300", "city": "PEORIA", "state": "IL", "zip": "61602", "phone": "309-677-5230"}, "mail-address": {"street1": "300 LIBERTY STREET", "city": "PEORIA", "state": "IL", "zip": "61602"}}]
CIPS, CILCORP, CILCO, IP 8-K, dated 06/07/2006
UNITED
      STATES
SECURITIES
      AND EXCHANGE COMMISSION
Washington,
      D.C. 20549
FORM
                8-K
CURRENT
      REPORT
Pursuant
      to Section 13 or 15(d) of the
Securities
      Exchange Act of 1934
Date
      of
      report (Date of earliest event reported):
June
                7, 2006
Commission
                File Number
Exact
                Name of Registrant as Specified in Charter;
State
                of Incorporation;
Address
                and Telephone Number
IRS
                Employer
Identification
                Number
1-3672
Central
                Illinois Public Service Company
(Illinois
                Corporation)
607
                East Adams Street
Springfield,
                Illinois 62739
(217)
                523-3600
37-
0211380
2-95569
CILCORP
                Inc.
(Illinois
                Corporation)
300
                Liberty Street
Peoria,
                Illinois 61602
(309)
                677-5271
37-1169387
1-2732
Central
                Illinois Light Company
(Illinois
                Corporation)
300
                Liberty Street
Peoria,
                Illinois 61602
(309)
                677-5271
37-0211050
1-3004
Illinois
                Power Company
(Illinois
                Corporation)
370
                South Main Street
Decatur,
                Illinois 62523
(217)
                424-6600
37-0344645
Check
      the
      appropriate box below if the Form 8-K filing is intended to simultaneously
      satisfy the filing obligation of the registrant under any of the following
      provisions:
[
 ]
      Written communications pursuant to Rule 425 under the Securities Act (17 CFR
      230.425)
[ 
]
      Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
      240.14a-12)
[
 ]
      Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange
      Act
      (17 CFR 240.14d-2(b))
[
      ]
      Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange
      Act
      (17 CFR 240.13e-4(c))
ITEM
      8.01
      Other Events.
Central
      Illinois Public Service Company, doing business as AmerenCIPS ("CIPS"), Central
      Illinois Light Company, doing business as AmerenCILCO ("CILCO"), and Illinois
      Power Company, doing business as AmerenIP ("IP"), each hereby file their
      Statement of Computation of Ratio of Earnings to Fixed Charges and Combined
      Fixed Charges and Preferred Stock Dividend Requirements for the three months
      ended March 31, 2006. CILCORP Inc. ("CILCORP") hereby files its Statement of
      Computation of Ratio of Earnings to Fixed Charges for the three months ended
      March 31, 2006.
ITEM
      9.01
      Financial Statements and Exhibits.
(d)
      Exhibits
Exhibit
Number
:
Title
:
12.1
CIPS
CIPS'
                Statement of Computation of Ratio of Earnings to Fixed
Charges
                and Combined Fixed
Charges
                and Preferred Stock
Dividend
                Requirements
12.2
CILCORP
CILCORP's
                Statement of Computation of Ratio of Earnings to
Fixed
                Charges
12.3
CILCO
CILCO's
                Statement of Computation of Ratio of Earnings to Fixed
Charges
                and Combined Fixed Charges and Preferred Stock
Dividend
                Requirements
12.4
IP
IP's
                Statement of Computation of Ratio of Earnings to Fixed
Charges
                and Combined Fixed Charges and Preferred Stock
Dividend
                Requirements
____________
This
      combined Form 8-K is being filed separately by Central Illinois Public Service
      Company, CILCORP Inc., Central Illinois Light Company and Illinois Power Company
      (each a "registrant"). Information contained herein relating to any individual
      registrant has been filed by such registrant on its own behalf. No registrant
      makes any representation as to information relating to any other
      registrant.
2
SIGNATURES
Pursuant
      to the requirements of the Securities Exchange Act of 1934, each registrant
      has
      duly caused this report to be signed on its behalf by the undersigned thereunto
      duly authorized. The signature for each undersigned company shall be deemed
      to
      relate only to matters having reference to such company or its
      subsidiaries.
CENTRAL
      ILLINOIS PUBLIC SERVICE COMPANY
(Registrant)
/s/
      Jerre E.
      Birdsong
Name:
      Jerre E. Birdsong
Title:
      Vice President and Treasurer
CILCORP
      Inc.
(Registrant)
/s/
      Jerre E.
      Birdsong
Name:
      Jerre E. Birdsong
Title:
      Vice President and Treasurer
CENTRAL
      ILLINOIS LIGHT COMPANY
(Registrant)
/s/
      Jerre E.
      Birdsong
Name:
      Jerre E. Birdsong
Title:
      Vice President and Treasurer
ILLINOIS
      POWER COMPANY
(Registrant)
/s/
      Jerre E.
      Birdsong
Name:
      Jerre E. Birdsong
Title:
      Vice President and Treasurer
Date:
      June 7, 2006
3
EXHIBIT
      INDEX
Exhibit
Number
:
Title
:
12.1
CIPS
CIPS'
                Statement of Computation of Ratio of Earnings to Fixed
Charges
                and Combined Fixed Charges and Preferred Stock
Dividend
                Requirements
12.2
CILCORP
CILCORP's
                Statement of Computation of Ratio of Earnings to
Fixed
                Charges
12.3
CILCO
CILCO's
                Statement of Computation of Ratio of Earnings to
Fixed
                Charges and Combined Fixed Charges and Preferred Stock
Dividend
                Requirements
12.4
IP
IP's
                Statement of Computation of Ratio of Earnings to Fixed
Charges
                and Combined Fixed Charges and Preferred Stock
Dividend
                Requirements
4