An employer that deferred the employee portion of Social Security tax under Notice 2020-65 must, when reporting total Social Security wages paid to an employee on Form W-2, Wage and Tax Statement, include any wages for which it deferred withholding and payment of employee Social Security tax in box 3 (Social Security wages) and/or box 7 (Social security tips). However, it should not include in box 4 (Social security tax withheld) any amount of deferred employee Social Security tax that has not been withheld.

Similarly, when reporting total Railroad Retirement Tax Act (RRTA) compensation, an employer should include any compensation for which it deferred withholding and payment of the employee Social Security tax equivalent of Tier 1 RRTA tax under Notice 2020-65 in box 14 of the 2020 Form W-2, Wage and Tax Statement. However, it should not include in box 14 any amount of deferred employee Tier 1 RRTA tax that has not been withheld. Employee RRTA tax deferred in 2020 under Notice 2020-65 that is withheld in 2021 and not reported on the 2020 Form W-2 should be reported in box 14 on Form W-2c for 2020. On Form W-2c, employers should adjust the amount previously reported as Tier 1 tax in box 14 of the Form W-2 to include the deferred amounts that were withheld in 2021. Employee copies of Forms W-2c should be furnished to employees, and  the employer should direct its employees to (or otherwise provide to them) the instructions for employees specific to this correction.

For employees:

If employees had two or more employers in 2020 and their Form W-2c for 2020 shows a correction to box 4 (or to box 14 for employees who pay RRTA tax) to account for employee Social Security (or Tier 1 RRTA tax) that was deferred in 2020 and withheld in 2021, they should use the amount of Social Security tax (or Tier 1 RRTA tax) withheld reported on the Form W-2c to determine whether they had excess Social Security tax (or Tier 1 RRTA tax) on wages (or compensation) paid in 2020. However, If they had only one employer during 2020 and their Form W-2c, Corrected Wages and Tax Statement, for 2020, only shows a correction to box 4 (or to box 14 for employees who pay RRTA tax) to account for employee Social Security (or Tier 1 RRTA tax) that was deferred in 2020 and withheld in 2021 pursuant to Notice 2020-65, no further steps are required.

If the corrected amount in box 4 of the Form W-2c for 2020 causes the total amount of employee Social Security tax (or equivalent portion of the Tier 1 RRTA tax) withheld by all of their employers to exceed the maximum amount ($8,537.40) of tax that they owe, or increases an already existing excess amount of employee Social Security tax (or Tier 1 RRTA tax withheld), then they should file Form 1040-X, Amended U.S. Individual Income Tax Return, to claim a credit for the excess Social Security tax (or Tier 1 RRTA tax) withheld.