Why do I have to pay quarterly taxes when I am retired anc widowed?

You could have taxable income, such as interest, dividends, stock sales, rental income, IRA distributions, or other items that are taxable. Do you have anything like that?

You might not have to. Who says you do? Was your husband self employed, and are you a recent widow? Talk to a tax preparer or accountant. Unless you want to say what kinds of income you have here.