When seniors must file
If you are unmarried and at least 65 years of age, then you must file an income tax return if your gross income is $11,700 or more. However, if you live on Social Security benefits, you don't include this in gross income. If this is the only income you receive, then your gross income equals zero, and you don't have to file a federal income tax return. But if you do earn other income that is not tax-exempt, then each year you must determine whether the total exceeds $11,700. If you are married and file a joint return with a spouse who is also 65 or older, you must file a return if your combined gross income is $22,900 or more. If your spouse is under 65 years old, then the threshold amount decreases to $21,700. Keep in mind that these income thresholds only apply to the 2014 tax year, and generally increase slightly each year.