CFR 26-31.6413(a)-2-2013 Internal revenue. Part31:Employment taxes and collection of income tax at source. Section31.6413(a)-2:Adjustments of overpayments.
(a) In general. (1) An employer who has overcollected or overpaid employee Federal Insurance Contributions Act (FICA) tax under section 3101 or employer FICA tax under section 3111, employee Railroad Retirement Tax (RRTA) tax under section 3201 or employer RRTA tax under section 3221, or income tax required under section 3402 to be withheld, and has repaid or reimbursed the amount of the overcollection of such tax to the employee, shall correct such error as provided in this section.