My son recently cashed out his 401(k). (He really didn't want to, but it was necessary). When completing the form, he accidentally checked to withhold an additional 25% tax instead of an additional 5% in addition to the required 20% withheld. He was told to check the box for 25% thinking that meant the 20% plus the additional 5%. This was entirely an error in completing the paperwork. Is there any way, such as an amended withdrawal form, etc., any way at all that he can get the money back without waiting until he files his tax return next year? Please reply with details, form numbers, etc. if there is a way this can be done. Thank you.
Unfortunately, it's a simple 'no'. Once the IRS has your money, you need to wait until early next year to settle up. He can increase his allowances via form W4, and have less money withheld from pay checks the rest of this year, but no chance for a lump sum return before tax time.
For sake of a comprehensive answer, early withdrawals are subject to a 10% penalty along with regular income tax. It sounds like the son is in the 15% bracket, and a total 25% would have been the right number to choose.