If I want to pay extra to IRS (in expectation of selling my house this year) do I need to document that anywhere?

[VolvoGirl]

Not on your 2020 return.  You just make an estimated payment for 2021. Use one of these 1040ES slips.  And you will need to manually enter it into your return next year.

https://www.irs.gov/pub/irs-pdf/f1040es.pdf 

[Opus 17]

If you make an electronic payment, you don’t need a paper voucher, since your payment is automatically linked to your social security number.  

www.irs.gov/payments

Select 2021 estimated taxes or 1040-ES as the reason for the payment.  

When you prepare your 2021 return, you will enter the estimated payment on the Deductions and Credits page under “Estimates and other taxes paid”.   If you over-paid your estimate, the excess will be added to your refund.  

[Mike9241]

if you are single and have lived in and owned the home for at least 2 years out of the 5 years before the sale unless you used the home sale exclusion within 2 years before this sale, you are entitled to exclude $250,000 of gain.  $500,000 if married and your spouse lived in the home for 2 years out of 5 before the sale. The spouse does not have to have an ownership interest.

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