Section 1.1461-1(b) of the US Internal Revenue Code requires a withholding agent (including Qualified Intermediaries (QIs)) to file a withholding tax return Form 1042 (Annual Withholding Tax Return for U.S. Source Income of Foreign Persons). A withholding agent must file Form 1042 on or before March 15 (unless an extension is sought) of the year following the calendar year in which the income was paid.
On February 23, 2023, the Department of the Treasury (Treasury Department) and the Internal Revenue Service (IRS) published final regulations introducing electronic filing requirements for Form 1042, effective for tax years beginning in 2024. However, the IRS had granted an exemption through Notice 2024-26 for tax year 2024, and this exemption has now expired.