@eled34 wrote:
Please note that I have a line-by-line statement from my employer detailing each overpaid amount for federal and state withholdings/deductions, insurance, 401(k), etcetera from the paycheck in which I received the overpayment. This should assist in calculating the exact amount I can reasonably expect back.
No. Withholding has almost nothing to do with the amount of tax you actually paid.
The only correct way to figure the credit is to re-calculate your 2019 tax return without the wages you repaid, and look at the difference in tax liability on form 1040, line 16. If your bonus was $40,000 and you repaid the entire amount, reduce your wages by that same $40,000 and see what the difference is in line 16. If you repaid less (for example, your employer adjusted for social security and medicare so you only repaid $36,940) then you base the credit calculation on the actual amount of cash out of pocket that you repaid, not the amount pre-adjustment.
You get your state taxes back by filing a claim of right claim on a state tax return, not the federal return. You will have to research the procedure for your state, assuming they even have one.
You may be able to get your social security and medicare taxes by filing a separate form 843, it is not part of your federal tax return (form 1040) and would be filed separately. You can actually file form 843 now, you don't have to wait for April 15 next year. But, you will need a written statement from your employer confirming that the employer is NOT adjusting or refunding your social security and medicare taxes, and you will need to include a letter of explanation and additional documentation such as copies of your original and corrected W-2s.
