Additional Medicare Tax and RRTA Tax Worksheet

If your employer withheld or you paid Additional Medicare Tax or Tier 1 RRTA taxes, use this worksheet to figure the amount to enter on line 21 of Schedule 8812 and line 7 of Credit Limit Worksheet B. Social security tax, Medicare tax, and Additional Medicare Tax on Wages. 1. Enter the social security tax withheld (Form(s) W-2, box 4, and Puerto Rico Form(s) 499R-2/W-2PR, box 21) 1. _____ 2. Enter the Medicare tax withheld (Form(s) W-2, box 6, and Puerto Rico Form(s) 499R-2/W-2PR, box 23). These boxes include any Additional Medicare Tax withheld 2. _____ 3. Enter any amount from Form 8959, line 7 3. _____ 4. Add lines 1, 2, and 3 4. _____ 5. Enter the Additional Medicare Tax withheld (Form 8959, line 22) 5. _____ 6. Subtract line 5 from line 4 6. _____ Additional Medicare Tax on Self-Employment Income. 7. Enter one-half of the Additional Medicare Tax, if any, on self-employment income (one-half of Form 8959, line 13) 7. _____ Tier 1 RRTA taxes as an employee of a railroad (enter amounts on lines 8, 9, 10, and 11) or employee representative (enter amounts on lines 12, 13, 14, and 15). Do not include amounts in Form W-2, box 14, that are identified as Additional Medicare Tax or Tier 2 tax. Do not include amounts shown on Form CT-2 on line 3 for Additional Medicare Tax or line 4 for Tier 2 tax. 8. Enter the Tier 1 tax (Form(s) W-2, box 14) 8. _____ 9. Enter the Medicare tax (Form(s) W-2, box 14) 9. _____ 10. Enter the Additional Medicare Tax, if any, on RRTA compensation as an employee (Form 8959, line 17). Do not use the same amount from Form 8959, line 17, for both this line 10 and line 14 10. _____ 11. Add lines 8, 9, and 10 11. _____ 12. Enter one-half of Tier 1 tax (one-half of Forms CT-2, line 1, for all 4 quarters of 2025) 12. _____ 13. Enter one-half of Tier 1 Medicare tax (one-half of Forms CT-2, line 2, for all 4 quarters of 2025) 13. _____ 14. Enter one-half of the Additional Medicare Tax, if any, on RRTA compensation as an employee representative (one-half of Form 8959, line 17). Do not use the same amount from Form 8959, line 17, for both this line 14 and line 10 14. _____ 15. Add lines 12, 13, and 14 15. _____ Line 21 Amount. 16. Add lines 6, 7, 11, and 15. Enter here and on line 21 of Schedule 8812 and, if applicable, line 7 of Credit Limit Worksheet B 16. _____