0000826732 2026-08-11 2026-08-11 0000826732 ck0000826732:doc_Calamos_High_Income_Opportunities_FundMember ck0000826732:S000004057Member 2026-08-11 2026-08-11 0000826732 ck0000826732:doc_Calamos_High_Income_Opportunities_FundMember ck0000826732:S000004057Member ck0000826732:C000011346Member 2026-08-11 2026-08-11 0000826732 ck0000826732:doc_Calamos_High_Income_Opportunities_FundMember ck0000826732:S000004057Member ck0000826732:C000011348Member 2026-08-11 2026-08-11 0000826732 ck0000826732:doc_Calamos_High_Income_Opportunities_FundMember ck0000826732:S000004057Member ck0000826732:C000011349Member 2026-08-11 2026-08-11 0000826732 ck0000826732:doc_Calamos_International_Growth_FundMember ck0000826732:S000004065Member 2026-08-11 2026-08-11 0000826732 ck0000826732:doc_CALAMOS_GLOBAL_EQUITY_FUNDMember ck0000826732:S000015914Member 2026-08-11 2026-08-11 pure iso4217:USD <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><span style="font-variant: small-caps"><b>CALAMOS INVESTMENT TRUST</b></span></p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">(the “Trust”)</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Supplement dated <span>August 11</span>, 2026 to the CALAMOS^® FAMILY OF FUNDS</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Prospectus and Statement of Additional Information, each dated February 27, 2026, as supplemented from time to time</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><i>This supplement updates certain information contained in the Prospectus and Statement of Additional Information noted above and should be attached to the Prospectus and Statement of Additional Information and retained for future reference.</i></p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <table cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; border-spacing: 0px;" width="100%"><tr style="vertical-align: top"> <td style="width: 0.25in"></td><td style="width: 0.25in">1.</td><td><span style="text-decoration:underline">Calamos High Income Opportunities Fund</span></td></tr></table><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p><table cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; border-spacing: 0px;" width="100%"><tr style="vertical-align: top"> <td style="width: 0.25in"></td><td style="width: 0.25in">2.</td><td><span style="text-decoration:underline">Calamos International Growth Fund and Calamos Global Equity Fund</span></td></tr></table> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><span style="font-variant: small-caps"><b>CALAMOS INVESTMENT TRUST</b></span></p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">(the “Trust”)</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Supplement dated <span>August 11</span>, 2026 to the CALAMOS^® FAMILY OF FUNDS</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Prospectus and Statement of Additional Information, each dated February 27, 2026, as supplemented from time to time</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><i>This supplement updates certain information contained in the Prospectus and Statement of Additional Information noted above and should be attached to the Prospectus and Statement of Additional Information and retained for future reference.</i></p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <table cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; border-spacing: 0px;" width="100%"><tr style="vertical-align: top"> <td style="width: 0.25in"></td><td style="width: 0.25in">1.</td><td><span style="text-decoration:underline">Calamos High Income Opportunities Fund</span></td></tr></table><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p><table cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; border-spacing: 0px;" width="100%"><tr style="vertical-align: top"> <td style="width: 0.25in"></td><td style="width: 0.25in">2.</td><td><span style="text-decoration:underline">Calamos International Growth Fund and Calamos Global Equity Fund</span></td></tr></table> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><span style="font-variant: small-caps"><b>CALAMOS INVESTMENT TRUST</b></span></p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">(the “Trust”)</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Supplement dated <span>August 11</span>, 2026 to the CALAMOS^® FAMILY OF FUNDS</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center">Prospectus and Statement of Additional Information, each dated February 27, 2026, as supplemented from time to time</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0; text-align: center"><i>This supplement updates certain information contained in the Prospectus and Statement of Additional Information noted above and should be attached to the Prospectus and Statement of Additional Information and retained for future reference.</i></p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <table cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; border-spacing: 0px;" width="100%"><tr style="vertical-align: top"> <td style="width: 0.25in"></td><td style="width: 0.25in">1.</td><td><span style="text-decoration:underline">Calamos High Income Opportunities Fund</span></td></tr></table><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p><table cellpadding="0" style="font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt; border-spacing: 0px;" width="100%"><tr style="vertical-align: top"> <td style="width: 0.25in"></td><td style="width: 0.25in">2.</td><td><span style="text-decoration:underline">Calamos International Growth Fund and Calamos Global Equity Fund</span></td></tr></table> 2026-02-27 Calamos High Income Opportunities Fund <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">The Annual Fund Operating Expenses table for Calamos High Income Opportunities Fund is restated as follows:</p> <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="font: bold 10pt Times New Roman, Times, Serif; border-bottom: Black 1pt solid"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt"><b>Annual Fund Operating Expenses (expenses that you pay each year <br/> as a percentage of the value of your investment):¹      </b></span></td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Class A</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Class C</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Class I</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 61%; font: 10pt Times New Roman, Times, Serif; text-align: left">Management Fee</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">0.60</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">0.60</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">0.60</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left">%</td></tr> <tr style="vertical-align: bottom; "> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left">Distribution and/or Service (12b-1) Fees</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">0.25</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">1.00</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">None</span></td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font: 10pt Times New Roman, Times, Serif"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Other Expenses</span></td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">0.90</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">0.90</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">0.90</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td></tr> <tr style="vertical-align: bottom; "> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left">Total Annual Fund Operating Expenses</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">1.75</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">2.50</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">1.50</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">%</td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font: 10pt Times New Roman, Times, Serif"><span style="font-family: Times New Roman, Times, Serif; font-size: 10pt">Expense Reimbursement²</span></td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">(0.75</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">)%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">(0.75</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">)%</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">(0.75</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left">)%</td></tr> <tr style="vertical-align: bottom; "> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left; padding-bottom: 1pt">Net Annual Fund Operating Expenses</td><td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: right">1.00</td><td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: right">1.75</td><td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">%</td><td style="font: 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: right">0.75</td><td style="padding-bottom: 1pt; font: 10pt Times New Roman, Times, Serif; text-align: left">%</td></tr> </table><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in">1      The table has been restated to reflect assets as of January 31, 2026.</p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.25in">2      The Fund's investment advisor has contractually agreed to reimburse Fund expenses through March 1, 2027 to the extent necessary so that Total Annual Fund Operating Expenses (excluding taxes, interest, short interest, short dividend expenses, brokerage commissions, acquired fund fees and expenses, and extra- ordinary expenses, if any) of Class A, Class C, and Class I are limited to 1.00%, 1.75%, and 0.75% of average net assets, respectively. Calamos Advisors LLC ("Calamos Advisors") may recapture previously waived expense amounts within the same fiscal year for any day where the respective Fund's expense ratio falls below the contractual expenses limit up to the expense limit for that day. This undertaking is binding on Calamos Advisors and any of its successors and assigns. This agreement is not terminable by either party.</p> Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment): 0.006 0.006 0.006 0.0025 0.01 0 0.009 0.009 0.009 0.0175 0.025 0.015 -0.0075 -0.0075 -0.0075 0.01 0.0175 0.0075 The table has been restated to reflect assets as of January 31, 2026. 2027-03-01 Example <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">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 either redeem or do not redeem your shares at the end of the reflected time periods. The example also assumes that your investment has a 5% return each year, that all dividends and capital gain distributions are reinvested, that you pay a maximum initial or contingent deferred sales charge and that the Fund's operating expenses remain the same. Any applicable fee waivers and/or expense reimbursements are reflected in the below examples for the period through March 1, 2027 only. Although your actual performance and costs may be higher or lower, based on these assumptions, your costs would be:</p> You would pay the following expenses if you redeemed your shares at the end of the period: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="font-size: 10pt"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">One Year</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Three Years</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Five Years</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Ten Years</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 48%; font: 10pt Times New Roman, Times, Serif; text-align: left">Class A</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">325</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">692</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">1,084</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">2,180</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td></tr> <tr style="vertical-align: bottom; "> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left">Class C</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">278</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">706</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">1,262</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">2,778</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left">Class I</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">77</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">400</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">747</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">1,726</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td></tr> </table><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">You would pay the following expenses if you did not redeem your shares:</p> 325 692 1084 2180 278 706 1262 2778 77 400 747 1726 You would pay the following expenses if you did not redeem your shares: <table cellpadding="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif; border-spacing: 0px;"> <tr style="vertical-align: bottom"> <td style="font-size: 10pt"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">One Year</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Three Years</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Five Years</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td><td style="font: bold 10pt Times New Roman, Times, Serif; padding-bottom: 1pt"> </td> <td colspan="2" style="font: bold 10pt Times New Roman, Times, Serif; text-align: center; border-bottom: Black 1pt solid">Ten Years</td><td style="padding-bottom: 1pt; font: bold 10pt Times New Roman, Times, Serif"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="width: 48%; font: 10pt Times New Roman, Times, Serif; text-align: left">Class A</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">325</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">692</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">1,084</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif"> </td> <td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="width: 10%; font: 10pt Times New Roman, Times, Serif; text-align: right">2,180</td><td style="width: 1%; font: 10pt Times New Roman, Times, Serif; text-align: left"> </td></tr> <tr style="vertical-align: bottom; "> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left">Class C</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">178</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">706</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">1,262</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">2,778</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td></tr> <tr style="vertical-align: bottom; background-color: rgb(204,238,255)"> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left">Class I</td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">77</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">400</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">747</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif"> </td> <td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td><td style="font: 10pt Times New Roman, Times, Serif; text-align: right">1,726</td><td style="font: 10pt Times New Roman, Times, Serif; text-align: left"> </td></tr> </table> 325 692 1084 2180 178 706 1262 2778 77 400 747 1726 Calamos International Growth Fund Calamos Global Equity Fund <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">The following is added as footnote 2 with respect to the “Management Fee” row in the Annual Fund Operating Expenses table for Calamos International Growth Fund (on page 71 of the Prospectus):</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.5in">“The Fund’s management fee is determined by calculating a base fee and applying a performance adjustment. The Fund's base fee is at the annual rate of 1.00% on the first $500 million, 0.95% on the next $500 million, 0.90% on the next $5 billion (over $1 billion to $6 billion), and 0.80% on average daily net assets in excess of $6 billion. The base fee is subject to adjustment, up or down, based on the Fund's performance relative to the performance of the MSCI EAFE Growth Index. Specifically, the performance adjustment equally increases or decreases the base fee, on a monthly basis, by 1/12 of 0.03% of the Fund's average daily net assets over the performance measurement period for each full 1% increment amount by which the Fund outperforms or underperforms the MSCI EAFE Growth Index over the performance measurement period on an annualized basis. The maximum monthly performance adjustment for each Fund is plus or minus 1/12 of 0.30% of the Fund's average daily net assets during the performance measurement period.”</p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0">The following is added as footnote 2 with respect to the “Management Fee” row in the Annual Fund Operating Expenses table for Calamos Global Equity Fund (on page 82 of the Prospectus):</p><p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0"> </p> <p style="font: 10pt Times New Roman, Times, Serif; margin: 0pt 0 0pt 0.5in">“The Fund’s management fee is determined by calculating a base fee and applying a performance adjustment. The Fund's base fee is at the annual rate of 1.00% on the first $500 million, 0.95% on the next $500 million, 0.90% on the next $5 billion (over $1 billion to $6 billion), and 0.80% on average daily net assets in excess of $6 billion. The base fee is subject to adjustment, up or down, based on the Fund's performance relative to the performance of the MSCI World Index. Specifically, the performance adjustment equally increases or decreases the base fee, on a monthly basis, by 1/12 of 0.03% of the Fund's average daily net assets over the performance measurement period for each full 1% increment amount by which the Fund outperforms or underperforms the MSCI World Index over the performance measurement period on an annualized basis. The maximum monthly performance adjustment for each Fund is plus or minus 1/12 of 0.30% of the Fund's average daily net assets during the performance measurement period.”</p> 497 N-1A 0000826732 false 2026-08-11 CALAMOS INVESTMENT TRUST/IL The Fund's investment advisor has contractually agreed to reimburse Fund expenses through March 1, 2027 to the extent necessary so that Total Annual Fund Operating Expenses (excluding taxes, interest, short interest, short dividend expenses, brokerage commissions, acquired fund fees and expenses, and extra- ordinary expenses, if any) of Class A, Class C, and Class I are limited to 1.00%, 1.75%, and 0.75% of average net assets, respectively. Calamos Advisors LLC ("Calamos Advisors") may recapture previously waived expense amounts within the same fiscal year for any day where the respective Fund's expense ratio falls below the contractual expenses limit up to the expense limit for that day. This undertaking is binding on Calamos Advisors and any of its successors and assigns. This agreement is not terminable by either party. The table has been restated to reflect assets as of January 31, 2026.