when applying for financial aid through the free application for federal student aid fafsa it is prudent to retain tax returns for at least two years the fafsa requires applicants to provide detailed financial information including income and tax details 
for individuals applying for government assistance programs consider keeping tax returns for at least three years some government assistance programs may require tax information to determine eligibility and calculate benefits by maintaining tax returns individuals ensure compliance with program requirements and can more quickly get the benefits they may need 