20 CFR 404.1275: Adjustment of employee contributions—for wages paid prior to 1987.

The amount of contributions a State deducts from an employee's remuneration for covered services, or any correction of that amount, is a matter between the employee and the State or political subdivision. The State shall show any correction of an employee's contribution on statements it furnishes the employee under § 404.1225 of this part. Where the State issues an employee a Form W-2 and then submits an overpayment adjustment but claims less than the total overpaid amount as a refund or credit, the State shall not correct the previously issued Form W-2 to reflect that adjustment.