In case you fail to fill in the tax, it is possible that the IRS can impose a Failure-to-File penalty that rises each month, and can reach as much as 25 percent of the tax owed. There is also interest charged on daily basis until one pays. You might lose an opportunity to take back the refunds or tax credits within three years. In other instances, the IRS may also prepare a Substitute for Return based on the information about the income, which in most cases leads to the increase in the tax return. Non-filing Long term non-filing may result in garnishment of wages, tax liens, seizure of assets and legal problems. On time filing avoids the needless penalties, stress and financial impact.  What Happens If You Don't File Taxes