Up to 85% of Social Security Retirement/Disability/Survivors benefits becomes taxable when all your other income plus 1/2 your social security reaches:

• Married Filing Jointly - $32,000
• Single or Head of Household - $25,000
• Married Filing Separately - 0

In your prior question, you mentioned an RMD. Be sure to count that amount  in the calculatoon..

Example 1: You  currently have $20,000 of Social security benefits and no other income.
$32,000 -10,000 (half of your SS) = 22,000. You may add $22,000 of capital gains or other income and your SS will still not be taxable

Example 2: You  currently have $20,000 of Social security benefits and $12,000 in RMD.
$32,000 – 12,000 (RMD) – 10,000 (half SS) = $10,000. You may add $10,000 of capital gains or other income and you SS will still not be taxable

RMD?

Required Minimum Distribution.  When you turn 70 1/2 you have to start taking the RMD from your IRA and 401K accounts.

"my only income is social security, and the required withdrawal since I am over 70-1/2"
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