Stock Sale

[intelman4]

This February, due to concerns about the virus effects on my stock price, I sold a significant amount. I had two questions:

1. Since this sale took place in the first quarter, when do I have to pay the taxes? Do I have to pay immediately, or can I wait until April 15th?
2. Since this stock sale is a long-term capital gains, and because I (retired) had no other source of income other than the qualified dividends I was receiving, why is it that my effective tax rate not zero? As I understood it, my tax bracket is determined before any capital gains.

[SusanY1]

You can wait to pay your estimates on any gain until the end of the quarter, or April 15. 

Your ordinary income tax rate(bracket) is determined before any capital gains, and it will not be raised as the result of your capital gains transactions.

However, your capital gains do count as part of your adjusted gross income, and it is possible for the capital gains transactions alone to cause your income to be high enough to kick you out of the 0% tax bracket on capital gains for at least a portion of that income.

For 2020, if you are a single tax filer, you will pay a 15% tax on your long term gains that exceded $40,001 and 20% on the amount that exceeds $441,451.  Married taxpayers filing jointly will pay 15% on gains in excess of $80,001 and 20% on the amount that exceeds $496,601.