0001722388 2026-04-29 2026-04-29 0001722388 vistashares:S000094435Member 2026-04-29 2026-04-29 0001722388 vistashares:S000094438Member 2026-04-29 2026-04-29 0001722388 vistashares:S000094435Member vistashares:IndexStrategyRisksMember 2026-04-29 2026-04-29 0001722388 vistashares:S000094438Member vistashares:IndexStrategyRisksMember 2026-04-29 2026-04-29 false TIDAL TRUST III N-1A 0001722388 497 2026-04-29 <div id="xdx_A84_eoef--SupplementToProspectusTextBlock_zykk4w6Lw1g8"></div> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: center"><b>Supplement to the Summary Prospectus and Prospectus,</b></p> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: center"><b>each dated <span id="xdx_90F_eoef--ProspectusDate_c20260429__20260429_zf5ZJZipYQff">August 18, 2025</span></b></p> <table cellpadding="0" cellspacing="0" style="font-size: 10pt; width: 100%; border-collapse: collapse"> <tr style="vertical-align: bottom"> <td style="border-bottom: black 1pt solid; font: 10pt Times New Roman,serif; width: 100%"> </td></tr> </table> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify"> </p> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify">The following disclosure changes apply only to the VistaShares ACKtivist Select ETF and the VistaShares Target 15 ACKtivist Distribution ETF and reflect a change to the methodology of the BITA VistaShares ACKtivist Select Index (the “Index”). Effective April 28, 2026, the Index underwent an extraordinary reconstitution to add shares of Pershing Square USA, Ltd. as a permanent constituent of the Index.</p> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify"> </p> 2025-08-18 <div id="xdx_A84_eoef--StrategyNarrativeTextBlock_zLcOHq2bMsoa"></div> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify">Effective immediately, for the VistaShares ACKtivist Select ETF, the second paragraph under the heading “Principal Investment Strategies” is amended and restated as follows:</p> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify"> </p> <p style="font: 10pt Times New Roman,serif; margin: 0 0.5in; text-align: justify">The Fund invests directly or indirectly in the equity securities that make up the Index (“Underlying Securities”). The Index is constructed by BITA GmbH (the “Index Provider”) using a rules-based methodology that identifies the top 20 U.S.-listed equity securities, to the extent available, as measured by their weight within Pershing Square’s portfolio, as publicly disclosed in its most recent most recent 13F filing, which generally will reflect Pershing Square’s holdings from the prior fiscal quarter. Companies that meet the criteria described above are included in the Index. The Index also includes an approximately 10% allocation to the stock of Pershing Square USA, Ltd. (NYSE: PSUS). As a result, the Index is generally expected to be comprised of between 11 and 21 constituents. The Index may include securities of small-, mid-, and large-capitalization companies.</p> <div id="xdx_A84_eoef--StrategyNarrativeTextBlock_zLcOHq2bMsfa"></div> <p style="font: 10pt Times New Roman,serif; margin: 0pt; text-align: justify">Effective immediately, for the VistaShares Target 15 ACKtivist Distribution ETF, the second paragraph under the heading “Principal Investment Strategies - Index Strategy” is amended and restated as follows:</p> <p style="font: 10pt Times New Roman,serif; margin: 0 0.5in 0 0; text-align: justify"> </p> <p style="font: 10pt Times New Roman,serif; margin: 0 0.5in; text-align: justify">The Index is constructed by BITA GmbH (the “Index Provider”) using a rules-based methodology that identifies the top 20 U.S.-listed equity securities, to the extent available, as measured by their weight within Pershing Square’s portfolio, as publicly disclosed in its most recent most recent 13F filing, which generally will reflect Pershing Square’s holdings from the prior fiscal quarter. Companies that meet the criteria described above are included in the Index. The Index also includes an approximately 10% allocation to the stock of Pershing Square USA, Ltd. (NYSE: PSUS). As a result, the Index is generally expected to be comprised of between 11 and 21 constituents. The Index may include securities of small-, mid-, and large-capitalization companies.</p> <div id="xdx_804_eoef--RiskTextBlock_hdei--LegalEntityAxis__custom--S000094435Member__oef--RiskAxis__custom--IndexStrategyRisksMember_dU_zr7yWcuiR8gj"></div> <div id="xdx_840_eoef--RiskTextBlock_hdei--LegalEntityAxis__custom--S000094438Member__oef--RiskAxis__custom--IndexStrategyRisksMember_dU_zW9ZhOtzogT7"></div> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify">Effective immediately, the risk disclosure “Index/Strategy Risks” under the heading “Principal Investment Risks” is supplemented by the addition of the following new paragraph:</p> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify"> </p> <p style="font: 10pt Times New Roman,serif; margin: 0 0.5in; text-align: justify">In addition, the Index includes an approximately 10% allocation to Pershing Square USA, Ltd. (the “Pershing Fund”), a non-diversified, closed-end management investment company. Investing in the Pershing Fund involves risks. Shareholders of the Fund do not have direct ownership of the securities held by the Pershing Fund and have no ability to influence the Pershing Fund’s investment decisions, which are made by the Pershing Fund’s investment manager. Shares of closed-end funds frequently trade at a discount or premium to their net asset value (“NAV”). The market price of the Pershing Fund’s shares will fluctuate in response to, among other things, changes in the value of the Pershing Fund’s portfolio holdings, supply and demand for shares, investor sentiment, and general market and economic conditions. As a result, the Pershing Fund’s shares may trade at a price that is higher or lower than NAV, and investors may experience losses independent of the performance of the Pershing Fund’s underlying assets. The Pershing Fund’s investment performance depends on the investment strategies and decisions of its investment manager. There can be no assurance that the investment manager’s strategies will achieve the Pershing Fund’s investment objective. The Pershing Fund may employ leverage, which may increase the volatility of the Pershing Fund’s returns and may magnify losses. An investment in the Pershing Fund is subject to risks inherent in equity investing and in the financial markets generally, including market volatility, interest rate risk, liquidity risk, and regulatory risk. The Pershing Fund’s shares may also be affected by factors unrelated to the performance of its portfolio, including market perceptions and trading activity.</p> <div id="xdx_840_eoef--RiskTextBlock_hdei--LegalEntityAxis__custom--S000094438Member__oef--RiskAxis__custom--IndexStrategyRisksMember_dU_zW9ZhOtzogT7"></div> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify">Effective immediately, the risk disclosure “Index/Strategy Risks” under the heading “Principal Investment Risks” is supplemented by the addition of the following new paragraph:</p> <p style="font: 10pt Times New Roman,serif; margin: 0; text-align: justify"> </p> <p style="font: 10pt Times New Roman,serif; margin: 0 0.5in; text-align: justify">In addition, the Index includes an approximately 10% allocation to Pershing Square USA, Ltd. (the “Pershing Fund”), a non-diversified, closed-end management investment company. Investing in the Pershing Fund involves risks. Shareholders of the Fund do not have direct ownership of the securities held by the Pershing Fund and have no ability to influence the Pershing Fund’s investment decisions, which are made by the Pershing Fund’s investment manager. Shares of closed-end funds frequently trade at a discount or premium to their net asset value (“NAV”). The market price of the Pershing Fund’s shares will fluctuate in response to, among other things, changes in the value of the Pershing Fund’s portfolio holdings, supply and demand for shares, investor sentiment, and general market and economic conditions. As a result, the Pershing Fund’s shares may trade at a price that is higher or lower than NAV, and investors may experience losses independent of the performance of the Pershing Fund’s underlying assets. The Pershing Fund’s investment performance depends on the investment strategies and decisions of its investment manager. There can be no assurance that the investment manager’s strategies will achieve the Pershing Fund’s investment objective. The Pershing Fund may employ leverage, which may increase the volatility of the Pershing Fund’s returns and may magnify losses. An investment in the Pershing Fund is subject to risks inherent in equity investing and in the financial markets generally, including market volatility, interest rate risk, liquidity risk, and regulatory risk. The Pershing Fund’s shares may also be affected by factors unrelated to the performance of its portfolio, including market perceptions and trading activity.</p>