If you haven't yet filed your federal tax return, it can certainly feel that way as the IRS filing deadline looms (April 15, 2019, for most taxpayers). By paying (or having paid through withholding and estimated taxes) 100%, you avoid interest and penalties. You should hurry with this, as the first quarter estimated tax payment is due the same day as your Form 1040 tax return! Penalties are calculated on a quarterly basis, so you must make estimated tax payments in the quarter when you earned the income. Details on estimated taxes, including a worksheet and all the due dates, are covered in the instructions for IRS Form 1040-ES.

Source: Forbes April 04, 2019 19:07 UTC