If you owe the government money (social security overpayment, student loans, etc. . . ) and they owe you a tax refund, the government can keep your tax refund to satisfy part of the debt you owe. This is called a set-off. A valid set-off is not subject to avoidance even if it happens in the 90 days before filing a bankruptcy. However, if the government takes your tax refund AFTER you have filed a chapter 7 or chapter 13 bankruptcy, this is a violation of the automatic stay and the government should return your tax refund to you. If they refuse to return the funds, you may have to file a motion with the Bankruptcy Court for return of the funds.