(a) In general. For purposes of subtitle F of the Internal Revenue Code (“Procedure and Administration”), the tax imposed under section 5000C on foreign persons is treated as a tax imposed under subtitle A. Except as provided elsewhere in the regulations under section 5000C, forms, or accompanying instructions, the tax imposed on foreign contracting parties under section 5000C is administered in a manner similar to gross basis income taxes. This section provides procedures that a foreign contracting party must follow to satisfy its obligations to report and deposit tax due under § 1.5000C-1 as well as procedures for contracting parties to seek a refund of amounts overwithheld.

(b) Tax obligation of foreign contracting party independent of withholding. A foreign contracting party subject to tax under section 5000C and §§ 1.5000C-1 through 1.5000C-7 remains liable for the tax unless its tax obligation was fully satisfied by withholding by an acquiring agency in accordance with §§ 1.5000C-2 and 1.5000C-3.

(c) Return of tax by the foreign contracting party. If the tax liability under § 1.5000C-1 relating to a payment is not fully satisfied by withholding in accordance with §§ 1.5000C-2 and 1.5000C-3 (including as a result of the use of an estimated nonexempt amount or estimated total contract price in computing the contract ratio), a foreign contracting party subject to tax under § 1.5000C-1 during a calendar year must make a return of tax on, for example, Form 1120-F, “U.S. Income Tax Return of a Foreign Corporation,” or such other form as the Internal Revenue Service (IRS) may prescribe to report the amount of tax due under section 5000C (required return). A foreign contracting party with no other U.S. tax filing obligation other than with respect to its liability for the tax imposed under section 5000C must file its required return on or before the fifteenth day of the sixth month following the close of its taxable year. The required return must include the information required by the form and accompanying instructions. The required return must be filed at the place and time (including any extension of time to file) provided by the form and accompanying instructions. Penalties for failure to file contained in Subtitle F can apply to foreign contracting parties who fail to file the required return. A foreign contracting party must attach copies of all Forms 1042-S, “Foreign Person's U.S. Source Income Subject to Withholding,” received from acquiring agencies (if any) to the required return.

(d) Time and manner of paying tax. A foreign contracting party must pay the tax imposed under section 5000C in the manner provided and in the time prescribed in the required return and accompanying instructions. In general, the foreign contracting party must pay the tax at the time that the required return is due, excluding extensions. To the extent provided in forms, instructions, or publications prescribed by the IRS, each foreign contracting party must deposit tax due under section 5000C by electronic funds transfer, as that term is defined in § 31.6302-1(h)(4)(i) of this chapter. A foreign contracting party that fails to pay tax in the time and manner prescribed in this section (or under forms, instructions, or publications prescribed by the IRS under this section) may be subject to penalties and interest under Subtitle F.

(e) Refund requests when amount withheld exceeds tax liability. After taking into account any offsets pursuant to § 1.5000C-2(e)(3), if the acquiring agency has overwithheld amounts under section 5000C and has made a deposit of the amounts under § 1.5000C-3(b), the contracting party may claim a refund of the amount overwithheld pursuant to the procedures described in chapter 65. The contracting party's claim for refund must meet the requirements of section 6402 and the regulations thereunder, as applicable, and must be filed before the expiration of the period of limitations on refund in section 6511 and the regulations thereunder. In general, the contracting party making a refund claim must file the required return to claim a refund, stating the grounds upon which the claim is based. A Section 5000C Certificate and a copy of the Form 1042-S received from the acquiring agency must be attached to the required return. For purposes of this section, an amount is overwithheld if the amount withheld from the payment pursuant to section 5000C and §§ 1.5000C-1 through 1.5000C-7 exceeds the contracting party's tax liability under § 1.5000C-1, regardless of whether the overwithholding was in error or appeared correct when it occurred. A U.S. person may seek a refund under this paragraph (e) even if it was treated as a foreign person under the rules in § 1.5000C-2 (for example, because it neither had a taxpayer identification number on file in the System for Award Management nor submitted Form W-9, “Request for Taxpayer Identification Number (TIN) and Certification,” to the acquiring agency).