dei_DocumentType

497

dei_EntityRegistrantName

FIRST TRUST EXCHANGE-TRADED ALPHADEX FUND

Entity Inv Company Type

dei_EntityInvCompanyType

N-1A

Document Creation Date

dei_DocumentCreationDate

Jun. 01, 2023

Supplement to Prospectus [Text Block]

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1.

Notwithstanding anything to the contrary in the Funds’ prospectus, the section entitled “Summary Information - First Trust Mid Cap Core AlphaDEX^® Fund - Annual Fund Operating Expenses” is replaced in its entirety with the following:

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Management Fees⁽¹⁾	0.50%
Distribution and Service (12b-1) Fees	0.00%
Other Expenses	0.09%
Total Annual Fund Operating Expenses	0.59%
Fee Waiver and Expense Reimbursement⁽²⁾	0.00%
Net Annual Fund Operating Expenses	0.59%

(1)

Effective November 1, 2022, as approved by the Trust’s Board of Trustees, the management fee paid to First Trust Advisors L.P., the Fund's investment advisor, will be reduced at certain levels of Fund net assets (“breakpoints”). See the Fund's Statement of Additional Information for more information on the breakpoints.

(2)

First Trust Advisors L.P., the Fund’s investment advisor, has agreed to waive fees and/or reimburse Fund expenses to the extent that the operating expenses of the Fund (excluding interest expense, brokerage commissions and other trading expenses, taxes and extraordinary expenses) exceed 0.70% of its average daily net assets (the “Expense Cap”) at least through November 30, 2023. Expenses reimbursed and fees waived under such agreement are subject to recovery by the Fund’s investment advisor for up to three years from the date the fee was waived or expense was incurred, but no recovery payment will be made by the Fund if it results in the Fund exceeding (i) the applicable expense limitation in place for the most recent fiscal year for which such expense limitation was in place, (ii) the applicable expense limitation in place at the time the fees were waived, or (iii) the current expense limitation. The agreement may be terminated by the Trust, on behalf of the Fund, at any time and by the Fund’s investment advisor only after November 30, 2023 upon 60 days’ written notice.

Example

The example below 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 hold or sell 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 at current levels. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$60	$189	$329	$738

Prospectus [Line Items]

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Supplement to Prospectus [Text Block]

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3.

Notwithstanding anything to the contrary in the Funds’ prospectus, the section entitled “Summary Information - First Trust Multi Cap Growth AlphaDEX® Fund - Annual Fund Operating Expenses” is replaced in its entirety with the following:

Annual Fund Operating Expenses
(expenses that you pay each year as a percentage of the value of your investment)

Management Fees⁽¹⁾	0.50%
Distribution and Service (12b-1) Fees	0.00%
Other Expenses	0.13%
Total Annual Fund Operating Expenses	0.63%
Fee Waiver and Expense Reimbursement⁽²⁾	0.00%
Net Annual Fund Operating Expenses	0.63%

(1)

Effective November 1, 2022, as approved by the Trust’s Board of Trustees, the management fee paid to First Trust Advisors L.P., the Fund's investment advisor, will be reduced at certain levels of Fund net assets (“breakpoints”). See the Fund's Statement of Additional Information for more information on the breakpoints.

(2)

First Trust Advisors L.P., the Fund’s investment advisor, has agreed to waive fees and/or reimburse Fund expenses to the extent that the operating expenses of the Fund (excluding interest expense, brokerage commissions and other trading expenses, taxes and extraordinary expenses) exceed 0.70% of its average daily net assets (the “Expense Cap”) at least through November 30, 2023. Expenses reimbursed and fees waived under such agreement are subject to recovery by the Fund’s investment advisor for up to three years from the date the fee was waived or expense was incurred, but no recovery payment will be made by the Fund if it results in the Fund exceeding (i) the applicable expense limitation in place for the most recent fiscal year for which such expense limitation was in place, (ii) the applicable expense limitation in place at the time the fees were waived, or (iii) the current expense limitation. The agreement may be terminated by the Trust, on behalf of the Fund, at any time and by the Fund’s investment advisor only after November 30, 2023 upon 60 days’ written notice.

Example

The example below 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 hold or sell 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 at current levels. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

1 Year	3 Years	5 Years	10 Years
$64	$202	$351	$786