"Living off my savings" is a bit vague. Even a savings account usually pays some interest, and that is considered taxable income. Selling stocks, gold, collectibles, or other investments to raise cash is reportable, and may be taxable if you sell for more than you paid. Withdrawals from retirement accounts are usually taxable.
If you really have no taxable income, or at least your taxable income is less than $13,800, then you are not required to file.
