If you don't file your taxes, several consequences can occur depending on whether you owe taxes or are due a refund. The IRS imposes a Failure to File penalty, which is typically 5% of the unpaid taxes for each month or partial month your return is late, up to a maximum of 25%. If you owe taxes and don't pay on time, you will also face a Failure to Pay penalty of 0.5% per month, which can add up to 25% of the unpaid tax. Interest accrues daily on any unpaid tax balance. The IRS may file a substitute return on your behalf that likely will not include any deductions or credits you may be entitled to. In severe cases of willful tax evasion or fraud, criminal penalties including jail time can apply. Additionally, the IRS may place a federal tax lien on your property, garnish wages, freeze bank accounts, or seize assets to collect owed taxes. If you are due a refund but don't file, you risk losing the chance to claim it if you wait too long, typically over three years. Ignoring tax filing obligations can also adversely affect future visa or green card applications if you are an international taxpayer.