Label

Element

Value

Robinson Alternative Yield Pre-Merger SPAC ETF

Prospectus [Line Items]

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Risk/Return [Heading]

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Robinson Alternative Yield Pre-Merger SPAC ETF

Supplement to Prospectus [Text Block]

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Robinson Alternative Yield Pre-Merger SPAC ETF

Trading Symbol: SPAX

listed on NYSE Arca, Inc.

Supplement dated December 17, 2021

to the Prospectus, Statement of Additional Information (“SAI”), and Summary Prospectus,

each dated June 21, 2021, as supplemented

Effective December 20, 2021, Toroso Investments, LLC (the “Adviser”), the investment adviser to the Robinson Alternative Yield Pre-Merger SPAC ETF (the “Fund”), has contractually agreed to reduce its unitary management fee from 0.85% to 0.50% of the Fund’s average daily net assets until at least December 19, 2022. In addition, the Fund is supplementing disclosure relating to the Fund’s principal investment strategies and principal risks.

The Fees and Expenses table and Expense Example on page 1 of each of the Prospectus and the Summary Prospectus are deleted and replaced with the following:

Expense [Heading]

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Fees and Expenses of the Fund

Expense Narrative [Text Block]

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This table describes the fees and expenses that you may pay if you buy, hold, and sell shares of the Fund (“Shares”). You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and Example below.

Fee Waiver or Reimbursement over Assets, Date of Termination

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December 19, 2022

Other Expenses, New Fund, Based on Estimates [Text]

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Estimated for the current fiscal year.

Expense Example [Heading]

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Expense Example

Expense Example Narrative [Text Block]

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This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other 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 and that the Fund’s operating expenses remain the same. The Example does not take into account brokerage commissions that you may pay on your purchases and sales of Shares. The management fee waiver discussed above is reflected only through December 19, 2022.

Expense Example by, Year, Caption [Text]

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Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Strategy [Heading]

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The following disclosure is added at the end of the fourth paragraph in the subsection titled “Principal Investment Strategies” of the Prospectus and Summary Prospectus:

Strategy Narrative [Text Block]

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If the Fund holds common stock of a SPAC that fails to complete a business combination in the pre-determined time frame, the Fund will be entitled to receive a pro rata share of the value of the trust account. Under normal market conditions, the Fund generally intends to hold between 75-100 SPAC positions at any given point in time.

Supplement Closing [Text Block]

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Please retain this Supplement with your Prospectus, SAI, and Summary Prospectus for future reference

Robinson Alternative Yield Pre-Merger SPAC ETF | Robinson Alternative Yield Pre-Merger SPAC ETF

Prospectus [Line Items]

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Trading Symbol

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SPAX

Management Fees (as a percentage of Assets)

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0.85%

Distribution and Service (12b-1) Fees

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none

Other Expenses (as a percentage of Assets):

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none

^[1]

Expenses (as a percentage of Assets)

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0.85%

Fee Waiver or Reimbursement

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(0.35%)

Net Expenses (as a percentage of Assets)

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0.50%

^[2]

Expense Example, with Redemption, 1 Year

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$ 51

Expense Example, with Redemption, 3 Years

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$ 160

[1] Estimated for the current fiscal year.

[2] The Fund’s investment adviser, Toroso Investments, LLC (the “Adviser”), has agreed to reduce its unitary management fee (which includes all expenses incurred by the Fund except for interest charges on any borrowings, dividends and other expenses on securities sold short, taxes, brokerage commissions and other expenses incurred in placing orders for the purchase and sale of securities and other investment instruments, acquired fund fees and expenses, accrued deferred tax liability, extraordinary expenses, distribution fees and expenses paid by the Fund under any distribution plan adopted pursuant to Rule 12b-1 under the 1940 Act, and the unified management fee payable to the Adviser (collectively, the “Excluded Expenses”)) to 0.50% of the Fund’s average daily net assets through at least December 19, 2022. To the extent the Fund incurs Excluded Expenses, Total Annual Fund Operating Expenses After Fee Waiver will be higher than 0.50%. This agreement may be terminated only by, or with the consent of, the Tidal ETF Trust’s (the “Trust”) Board of Trustees (the “Board”), on behalf of the Fund, upon sixty (60) days’ written notice to the Adviser. This Agreement may not be terminated by the Adviser without the consent of the Board.