0000816153 tit2:S000011851Member tit2:C000056390Member 2011-02-02 2012-02-01 0000816153 tit2:S000020097Member tit2:C000056390Member 2011-02-02 2012-02-01 0000816153 tit2:S000011851Member tit2:C000056389Member 2011-02-02 2012-02-01 0000816153 tit2:S000011851Member 2011-02-02 2012-02-01 0000816153 tit2:S000020097Member 2011-02-02 2012-02-01 0000816153 tit2:S000011851Member tit2:C000056391Member 2011-02-02 2012-02-01 0000816153 tit2:S000020097Member tit2:C000056389Member 2011-02-02 2012-02-01 0000816153 tit2:S000020097Member tit2:C000056391Member 2011-02-02 2012-02-01 0000816153 2011-02-02 2012-02-01 pure iso4217:USD 1179 1109 1179 1212 Example. Example. 617 1155 1109 564 You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in “Opening Your Account—Buying Fund Shares” on page 71 of this Prospectus. You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in “Opening Your Account—Buying Fund Shares” on page 71 of this Prospectus. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over”) its portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 48.09% of the average value of its portfolio. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over”) its portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Fund’s performance. During the most recent fiscal year, the Fund’s portfolio turnover rate was 30.34% of the average value of its portfolio. 0.045 0 0 0.045 0 0 592 318 114 575 50000 50000 Shareholder Fees (fees paid directly from your investment) Shareholder Fees (fees paid directly from your investment) Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) Other THORNBURG INVESTMENT TRUST 2012-10-02 0 0.01 0 0 0.01 0 -0.0027 -0.0007 -0.0006 287 105 891 685 356 855 635 218 187 2539 2420 This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in “Opening Your Account—Buying Fund Shares” on page 71 of this Prospectus. This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in “Opening Your Account—Buying Fund Shares” on page 71 of this Prospectus. A 1.00% contingent deferred sales charge (CDSC) is imposed on redemptions of any part or all of a purchase of $1 million or more within 12 months of purchase. A 1.00% contingent deferred sales charge (CDSC) is imposed on redemptions of any part or all of a purchase of $1 million or more within 12 months of purchase. This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, dividends and distributions are reinvested, and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions (and giving effect to fee waivers and expense reimbursements in the first year), your costs would be: This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, dividends and distributions are reinvested, and that the Fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions (and giving effect to fee waivers and expense reimbursements in the first year), your costs would be: 2012-02-01 2011-09-30 0000816153 false 2012-10-02 0.0071 0.0071 0.0071 0.0075 0.0075 0.0075 0 0.01 0.0025 0 0.01 0.0025 0.0023 0.0032 0.0032 0.0016 0.0025 0.0025 0.0004 0.0004 0.0004 0.0025 0.0025 0.0025 0.0146 0.0221 0.0112 0.0136 0.0211 0.0102 0.0146 0.0215 0.0112 0.0129 0.0184 0.0102 326 2118 2539 1363 2006 2420 1249 685 635 SUPPLEMENT dated October 2, 2012 TO THE THORNBURG FUNDS PROSPECTUS dated February 1, 2012 The disclosures on page 31 of the Prospectus, under the caption Fees and Expenses of the Fund for the Thornburg Strategic Income Fund, are deleted and replaced with the disclosures which appear below. The replacement disclosures presented in this Supplement for the Fund add the Acquired Fund Fees and Expenses line and figures to the Annual Fund Operating Expenses table below, resulting in an increase in the Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement figure displayed for each share class. The described disclosures were inadvertently omitted from the Prospectus. This Supplement also provides an explanation of Acquired Fund Fees and Expenses in the narrative following the Example below.   <div style="position:relative;float:left; margin-right:1%; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> Fees and Expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in Opening Your AccountBuying Fund Shares on page 71 of this Prospectus. Shareholder Fees (fees paid directly from your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="63%"></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">4.50</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr> <td valign="top"> Maximum Deferred Sales Charge (Load) (as a percentage of redemption proceeds or original purchase price, whichever is lower)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap">(1) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">%(2) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="64%"></td> <td valign="bottom" width="11%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="10%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="10%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Management Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.75</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.75</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.75</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Distribution and Service (12b-1) Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.00</td> <td nowrap="nowrap">% </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Other Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.32</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.32</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.23</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Acquired Fund Fees and Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.04</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.04</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.04</td> <td nowrap="nowrap">% </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.36</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">2.11</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.02</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Fee Waiver/Expense Reimbursement</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">(0.07</td> <td nowrap="nowrap">)%(3) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">(0.27</td> <td nowrap="nowrap">)%(3) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">  </td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement(4)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.29</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.84</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.02</td> <td nowrap="nowrap">% </td></tr> </table>   <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(1)</td> <td align="left" valign="top">A 1.00% contingent deferred sales charge (CDSC) is imposed on redemptions of any part or all of a purchase of $1 million or more within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(2)</td> <td align="left" valign="top">Imposed only on redemptions of Class C shares within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(3)</td> <td align="left" valign="top">Thornburg Investment Management, Inc. (Thornburg) and Thornburg Securities Corporation (TSC) have contractually agreed to waive fees and reimburse expenses incurred by the Fund so that actual Class A and Class C expenses do not exceed 1.25% and 1.80%, respectively, not including the effects of Acquired Fund Fees and Expenses. The agreement to waive fees and reimburse expenses may be terminated by the Fund at any time, but may not be terminated by Thornburg or TSC before February 1, 2013, unless Thornburg or TSC ceases to be the investment advisor or distributor of the Fund prior to that date. </td></tr></table></div><div style="position:relative;float:right; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(4)</td> <td align="left" valign="top">The figures for Total Fund Operating Expenses After Fee Waiver/Expense Reimbursement in this table have been restated to add amounts for Acquired Fund Fees and Expenses, in accordance with regulatory rules. Acquired Fund Fees and Expenses vary with changes in the amount of the Funds investments in investment companies and other factors. Please see the disclosure below under the caption Explanation of Acquired Fund Fees and Expenses for a further explanation. </td></tr></table> Example. This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, dividends and distributions are reinvested, and that the Funds operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions (and giving effect to fee waivers and expense reimbursements in the first year), your costs would be:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class A Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">575</td> <td nowrap="nowrap" valign="bottom">  </td> <td>  </td> <td>$</td> <td align="right">855</td> <td nowrap="nowrap">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,155</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,006</td> <td nowrap="nowrap">  </td></tr> <tr> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">287</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">635</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,109</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,420</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class I Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">105</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">326</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">564</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,249</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> You would pay the following expenses if you did not redeem your Class C shares:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">187</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">635</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,109</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,420</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Explanation of Acquired Fund Fees and Expenses. Acquired Fund Fees and Expenses shown in the Annual Fund Operating Expenses table in the left-hand column are expenses incurred indirectly by other investment companies, such as business development companies, in which the Fund may hold shares. These operating expenses are similar to the expenses paid by other businesses owned by the Fund, are not direct costs paid by Fund shareholders, and are not used to calculate the Funds net asset value. These expenses have no impact on the costs associated with Fund operations. Regulatory rules require that the Acquired Fund Fees and Expenses be added to the actual operating expenses of the Fund, and that the total be shown in the bottom line of the Annual Fund Operating Expenses table in the left-hand column. Please see the expense figures shown in the Financial Highlights for the Fund, at pages 106 107, for a clearer picture of the Funds actual operating costs. Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or turns over) its portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Funds performance. During the most recent fiscal year, the Funds portfolio turnover rate was 48.09% of the average value of its portfolio. </div><div style="position:relative;float:right; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> </div><div style="clear:both; height:0px; font-size:0px"> </div>     The disclosures on page 51 of the Prospectus, under the caption Fees and Expenses of the Fund for the Thornburg Investment Income Builder Fund, are deleted and replaced with the disclosures which appear below. The replacement disclosures presented in this Supplement for the Fund add the Acquired Fund Fees and Expenses line and figures to the Annual Fund Operating Expenses table below, resulting in an increase in the Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement figure displayed for each share class. The described disclosures were inadvertently omitted from the Prospectus. This Supplement also provides an explanation of Acquired Fund Fees and Expenses in the narrative following the Example below.   <div style="position:relative;float:left; margin-right:1%; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> Fees and Expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in Opening Your AccountBuying Fund Shares on page 71 of this Prospectus. Shareholder Fees (fees paid directly from your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="63%"></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">4.50</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr> <td valign="top"> Maximum Deferred Sales Charge (Load) (as a percentage of redemption proceeds or original purchase price, whichever is lower)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap">(1) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">%(2) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="65%"></td> <td valign="bottom" width="10%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Management Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.71</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.71</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.71</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Distribution and Service (12b-1) Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.00</td> <td nowrap="nowrap">% </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Other Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.16</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Acquired Fund Fees and Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.46</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">2.21</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.12</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Fee Waiver/Expense Reimbursement</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">  </td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">(0.06</td> <td nowrap="nowrap">)%(3) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">  </td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement(4)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.46</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">2.15</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.12</td> <td nowrap="nowrap">% </td></tr> </table>   <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(1)</td> <td align="left" valign="top">A 1.00% contingent deferred sales charge (CDSC) is imposed on redemptions of any part or all of a purchase of $1 million or more within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(2)</td> <td align="left" valign="top">Imposed only on redemptions of Class C shares within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(3)</td> <td align="left" valign="top">Thornburg Investment Management, Inc. (Thornburg) and Thornburg Securities Corporation (TSC) have contractually agreed to waive fees and reimburse expenses incurred by the Fund so that actual Class C expenses do not exceed 1.90%, not including the effects of Acquired Fund Fees and Expenses. The agreement to waive fees and reimburse expenses may be terminated by the Fund at any time, but may not be terminated by Thornburg or TSC before February 1, 2013, unless Thornburg or TSC ceases to be the investment advisor or distributor of the Fund prior to that date. </td></tr></table></div><div style="position:relative;float:right; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(4)</td> <td align="left" valign="top">The figures for Total Fund Operating Expenses After Fee Waiver/Expense Reimbursement in this table have been restated to add amounts for Acquired Fund Fees and Expenses, in accordance with regulatory rules. Acquired Fund Fees and Expenses vary with changes in the amount of the Funds investments in investment companies and other factors. Please see the disclosure below under the caption Explanation of Acquired Fund Fees and Expenses for a further explanation. </td></tr></table> Example. This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, dividends and distributions are reinvested, and that the Funds operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions (and giving effect to fee waivers and expense reimbursements in the first year), your costs would be:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class A Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">592</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">891</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,212</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,118</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">318</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">685</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,179</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,539</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class I Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">114</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">356</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">617</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,363</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> You would pay the following expenses if you did not redeem your Class C shares:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">218</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">685</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,179</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,539</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Explanation of Acquired Fund Fees and Expenses. Acquired Fund Fees and Expenses shown in the table in the left-hand column are expenses incurred indirectly by other investment companies, such as business development companies, in which the Fund may hold shares. These operating expenses are similar to the expenses paid by other businesses owned by the Fund, are not direct costs paid by Fund shareholders, and are not used to calculate the Funds net asset value. These expenses have no impact on the costs associated with Fund operations. Regulatory rules require that the Acquired Fund Fees and Expenses be added to the actual operating expenses of the Fund, and that the total be shown in the bottom line of the Annual Fund Operating Expenses table in the left-hand column. Please see the expense figures shown in the Financial Highlights for the Fund, at pages 116 117, for a clearer picture of the Funds actual operating costs. Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or turns over) its portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Funds performance. During the most recent fiscal year, the Funds portfolio turnover rate was 30.34% of the average value of its portfolio. </div><div style="clear:both; height:0px; font-size:0px"> </div> SUPPLEMENT dated October 2, 2012 TO THE THORNBURG FUNDS PROSPECTUS dated February 1, 2012   The disclosures on page 51 of the Prospectus, under the caption Fees and Expenses of the Fund for the Thornburg Investment Income Builder Fund, are deleted and replaced with the disclosures which appear below. The replacement disclosures presented in this Supplement for the Fund add the Acquired Fund Fees and Expenses line and figures to the Annual Fund Operating Expenses table below, resulting in an increase in the Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement figure displayed for each share class. The described disclosures were inadvertently omitted from the Prospectus. This Supplement also provides an explanation of Acquired Fund Fees and Expenses in the narrative following the Example below.   <div style="position:relative;float:left; margin-right:1%; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> Fees and Expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in Opening Your AccountBuying Fund Shares on page 71 of this Prospectus. Shareholder Fees (fees paid directly from your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="63%"></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">4.50</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr> <td valign="top"> Maximum Deferred Sales Charge (Load) (as a percentage of redemption proceeds or original purchase price, whichever is lower)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap">(1) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">%(2) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="65%"></td> <td valign="bottom" width="10%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Management Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.71</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.71</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.71</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Distribution and Service (12b-1) Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.00</td> <td nowrap="nowrap">% </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Other Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.16</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Acquired Fund Fees and Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.46</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">2.21</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.12</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Fee Waiver/Expense Reimbursement</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">  </td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">(0.06</td> <td nowrap="nowrap">)%(3) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">  </td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement(4)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.46</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">2.15</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.12</td> <td nowrap="nowrap">% </td></tr> </table>   <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(1)</td> <td align="left" valign="top">A 1.00% contingent deferred sales charge (CDSC) is imposed on redemptions of any part or all of a purchase of $1 million or more within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(2)</td> <td align="left" valign="top">Imposed only on redemptions of Class C shares within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(3)</td> <td align="left" valign="top">Thornburg Investment Management, Inc. (Thornburg) and Thornburg Securities Corporation (TSC) have contractually agreed to waive fees and reimburse expenses incurred by the Fund so that actual Class C expenses do not exceed 1.90%, not including the effects of Acquired Fund Fees and Expenses. The agreement to waive fees and reimburse expenses may be terminated by the Fund at any time, but may not be terminated by Thornburg or TSC before February 1, 2013, unless Thornburg or TSC ceases to be the investment advisor or distributor of the Fund prior to that date. </td></tr></table></div><div style="position:relative;float:right; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(4)</td> <td align="left" valign="top">The figures for Total Fund Operating Expenses After Fee Waiver/Expense Reimbursement in this table have been restated to add amounts for Acquired Fund Fees and Expenses, in accordance with regulatory rules. Acquired Fund Fees and Expenses vary with changes in the amount of the Funds investments in investment companies and other factors. Please see the disclosure below under the caption Explanation of Acquired Fund Fees and Expenses for a further explanation. </td></tr></table> Example. This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, dividends and distributions are reinvested, and that the Funds operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions (and giving effect to fee waivers and expense reimbursements in the first year), your costs would be:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class A Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">592</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">891</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,212</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,118</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">318</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">685</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,179</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,539</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class I Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">114</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">356</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">617</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,363</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> You would pay the following expenses if you did not redeem your Class C shares:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">218</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">685</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,179</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,539</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Explanation of Acquired Fund Fees and Expenses. Acquired Fund Fees and Expenses shown in the table in the left-hand column are expenses incurred indirectly by other investment companies, such as business development companies, in which the Fund may hold shares. These operating expenses are similar to the expenses paid by other businesses owned by the Fund, are not direct costs paid by Fund shareholders, and are not used to calculate the Funds net asset value. These expenses have no impact on the costs associated with Fund operations. Regulatory rules require that the Acquired Fund Fees and Expenses be added to the actual operating expenses of the Fund, and that the total be shown in the bottom line of the Annual Fund Operating Expenses table in the left-hand column. Please see the expense figures shown in the Financial Highlights for the Fund, at pages 116 117, for a clearer picture of the Funds actual operating costs. Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or turns over) its portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Funds performance. During the most recent fiscal year, the Funds portfolio turnover rate was 30.34% of the average value of its portfolio. </div><div style="clear:both; height:0px; font-size:0px"> </div> SUPPLEMENT dated October 2, 2012 TO THE THORNBURG FUNDS PROSPECTUS dated February 1, 2012 The disclosures on page 31 of the Prospectus, under the caption Fees and Expenses of the Fund for the Thornburg Strategic Income Fund, are deleted and replaced with the disclosures which appear below. The replacement disclosures presented in this Supplement for the Fund add the Acquired Fund Fees and Expenses line and figures to the Annual Fund Operating Expenses table below, resulting in an increase in the Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement figure displayed for each share class. The described disclosures were inadvertently omitted from the Prospectus. This Supplement also provides an explanation of Acquired Fund Fees and Expenses in the narrative following the Example below.   <div style="position:relative;float:left; margin-right:1%; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> Fees and Expenses of the Fund This table describes the fees and expenses that you may pay if you buy and hold shares of the Fund. You may qualify for discounts from the sales charges applicable to Class A shares if you or other qualifying account holders invest, or agree to invest in the future, at least $50,000 in the Thornburg Funds. More information about these and other discounts is available from your financial professional and in Opening Your AccountBuying Fund Shares on page 71 of this Prospectus. Shareholder Fees (fees paid directly from your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="63%"></td> <td valign="bottom" width="9%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="8%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Maximum Sales Charge (Load) Imposed on Purchases (as a percentage of offering price)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">4.50</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr> <td valign="top"> Maximum Deferred Sales Charge (Load) (as a percentage of redemption proceeds or original purchase price, whichever is lower)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap">(1) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">%(2) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">none</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="64%"></td> <td valign="bottom" width="11%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="10%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="10%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class A</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class C</td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">Class I</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Management Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.75</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.75</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.75</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Distribution and Service (12b-1) Fees</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.25</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.00</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.00</td> <td nowrap="nowrap">% </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Other Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.32</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.32</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.23</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Acquired Fund Fees and Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">0.04</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.04</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">0.04</td> <td nowrap="nowrap">% </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.36</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">2.11</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.02</td> <td nowrap="nowrap">% </td></tr> <tr> <td valign="top"> Fee Waiver/Expense Reimbursement</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">(0.07</td> <td nowrap="nowrap">)%(3) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">(0.27</td> <td nowrap="nowrap">)%(3) </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">  </td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr style="font-size:1px"> <td valign="bottom"></td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom">  </td> <td> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Total Annual Fund Operating Expenses After Fee Waiver/Expense Reimbursement(4)</td> <td valign="bottom">  </td> <td valign="bottom"> </td> <td align="right">1.29</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.84</td> <td nowrap="nowrap">% </td> <td valign="bottom"> </td> <td valign="bottom"> </td> <td align="right">1.02</td> <td nowrap="nowrap">% </td></tr> </table>   <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(1)</td> <td align="left" valign="top">A 1.00% contingent deferred sales charge (CDSC) is imposed on redemptions of any part or all of a purchase of $1 million or more within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(2)</td> <td align="left" valign="top">Imposed only on redemptions of Class C shares within 12 months of purchase. </td></tr></table> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(3)</td> <td align="left" valign="top">Thornburg Investment Management, Inc. (Thornburg) and Thornburg Securities Corporation (TSC) have contractually agreed to waive fees and reimburse expenses incurred by the Fund so that actual Class A and Class C expenses do not exceed 1.25% and 1.80%, respectively, not including the effects of Acquired Fund Fees and Expenses. The agreement to waive fees and reimburse expenses may be terminated by the Fund at any time, but may not be terminated by Thornburg or TSC before February 1, 2013, unless Thornburg or TSC ceases to be the investment advisor or distributor of the Fund prior to that date. </td></tr></table></div><div style="position:relative;float:right; width:48%;padding-right:9px;padding-bottom:8px;overflow:hidden;padding-top:3px"> <table style="border-collapse:collapse" border="0" cellpadding="0" cellspacing="0" width="100%"> <tr> <td width="27" valign="top" align="left">(4)</td> <td align="left" valign="top">The figures for Total Fund Operating Expenses After Fee Waiver/Expense Reimbursement in this table have been restated to add amounts for Acquired Fund Fees and Expenses, in accordance with regulatory rules. Acquired Fund Fees and Expenses vary with changes in the amount of the Funds investments in investment companies and other factors. Please see the disclosure below under the caption Explanation of Acquired Fund Fees and Expenses for a further explanation. </td></tr></table> Example. This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year, dividends and distributions are reinvested, and that the Funds operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions (and giving effect to fee waivers and expense reimbursements in the first year), your costs would be:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class A Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">575</td> <td nowrap="nowrap" valign="bottom">  </td> <td>  </td> <td>$</td> <td align="right">855</td> <td nowrap="nowrap">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,155</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,006</td> <td nowrap="nowrap">  </td></tr> <tr> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">287</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">635</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,109</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,420</td> <td nowrap="nowrap" valign="bottom">  </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class I Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">105</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">326</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">564</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,249</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> You would pay the following expenses if you did not redeem your Class C shares:   <table cellspacing="0" cellpadding="0" width="100%" border="0" style="border-collapse:collapse" align="center"> <tr> <td width="50%"></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td> <td valign="bottom" width="7%"></td> <td></td> <td></td> <td></td></tr> <tr> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">1 Year</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">3 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">5 Years</td> <td valign="bottom"> </td> <td valign="bottom">  </td> <td valign="bottom" colspan="2" align="center" style="border-bottom:1px solid #000000">10 Years</td> <td valign="bottom"> </td></tr> <tr bgcolor="#cceeff"> <td valign="top"> Class C Shares</td> <td valign="bottom">  </td> <td>$</td> <td align="right">187</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">635</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">1,109</td> <td nowrap="nowrap" valign="bottom">  </td> <td valign="bottom">  </td> <td>$</td> <td align="right">2,420</td> <td nowrap="nowrap" valign="bottom">  </td></tr> </table> Explanation of Acquired Fund Fees and Expenses. Acquired Fund Fees and Expenses shown in the Annual Fund Operating Expenses table in the left-hand column are expenses incurred indirectly by other investment companies, such as business development companies, in which the Fund may hold shares. These operating expenses are similar to the expenses paid by other businesses owned by the Fund, are not direct costs paid by Fund shareholders, and are not used to calculate the Funds net asset value. These expenses have no impact on the costs associated with Fund operations. Regulatory rules require that the Acquired Fund Fees and Expenses be added to the actual operating expenses of the Fund, and that the total be shown in the bottom line of the Annual Fund Operating Expenses table in the left-hand column. Please see the expense figures shown in the Financial Highlights for the Fund, at pages 106 107, for a clearer picture of the Funds actual operating costs. Portfolio Turnover. The Fund pays transaction costs, such as commissions, when it buys and sells securities (or turns over) its portfolio. A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in Annual Fund Operating Expenses or in the Example, affect the Funds performance. During the most recent fiscal year, the Funds portfolio turnover rate was 48.09% of the average value of its portfolio. </div> Fees and Expenses of the Fund Fees and Expenses of the Fund February 1, 2013 February 1, 2013 You would pay the following expenses if you did not redeem your Class C shares: You would pay the following expenses if you did not redeem your Class C shares: Portfolio Turnover. Portfolio Turnover. 0.4809 0.3034 A 1.00% contingent deferred sales charge (CDSC) is imposed on redemptions of any part or all of a purchase of $1 million or more within 12 months of purchase. Imposed only on redemptions of Class C shares within 12 months of purchase. Thornburg Investment Management, Inc. ("Thornburg") and Thornburg Securities Corporation ("TSC") have contractually agreed to waive fees and reimburse expenses incurred by the Fund so that actual Class A and Class C expenses do not exceed 1.25% and 1.80%, respectively, not including the effects of Acquired Fund Fees and Expenses. The agreement to waive fees and reimburse expenses may be terminated by the Fund at any time, but may not be terminated by Thornburg or TSC before February 1, 2013, unless Thornburg or TSC ceases to be the investment advisor or distributor of the Fund prior to that date. The figures for Total Fund Operating Expenses After Fee Waiver/Expense Reimbursement in this table have been restated to add amounts for "Acquired Fund Fees and Expenses," in accordance with regulatory rules. Acquired Fund Fees and Expenses vary with changes in the amount of the Fund's investments in investment companies and other factors. Please see the disclosure below under the caption "Explanation of Acquired Fund Fees and Expenses" for a further explanation. Thornburg Investment Management, Inc. ("Thornburg") and Thornburg Securities Corporation ("TSC") have contractually agreed to waive fees and reimburse expenses incurred by the Fund so that actual Class C expenses do not exceed 1.90%, not including the effects of Acquired Fund Fees and Expenses. The agreement to waive fees and reimburse expenses may be terminated by the Fund at any time, but may not be terminated by Thornburg or TSC before February 1, 2013, unless Thornburg or TSC ceases to be the investment advisor or distributor of the Fund prior to that date.