Making an estimates tax payment

[chasker]

I need to make a pre-payment due to some stock sales and other unexpected income. However, I have missed 3 of the 4 deadlines for 2020. Should I adjust the amount on a voucher and send in one payment (anyway)? Or is there a better way to manage the payment? I'm trying to avoid the penalties as much as possible

[Carl]

If you make at estimated payment of "AT LEAST" 20% of the unexpected and as-of-yet untaxed income, then come tax filing time you should be fine.

If you had untaxed income in the first three quarters that you did not make quarterly payments on yet, then make one lump sum payment as soon as possible if not sooner, so as to stop the potential accumulation of late payment penalties.

Then at tax filing time (and not before) you may be able to reduce any potential penalties (if not eliminate them entirely) by quantifying the income for each quarter. That's done under the "Other Tax Situations" tab in the section for quarterly tax payments.

When you make the payment you are about to make "right now", make it your 2020 3rd quarter payment which was due on Sept 15, 2020. That leaves you room for your 4th quarter payment, which has a due date of Jan 15, 2021, in case you recieve any more untaxed income between now and Dec 31st.

You can make your payment immediately online at www.irs.gov/payments.