Filing after 65. A taxpayer usually don't have to file if her gross income is less than the annual limit set by the IRS. Filing status determines which limit applies. Of course, if you are due a refund because you had payroll taxes deducted or are entitled to a tax credit, you'll want to file anyway. The limit amounts change yearly because of inflation. For instance, these were the thresholds if you were 65 or older in 2014: Single filing status: $11,700.