How many percent tax on social security income?

[DoninGA]

Your Social Security wages reported on box 3 of the W-2 are taxed at 6.2% and the taxable amount is reported in box 4.

[VolvoGirl]

Or are you asking about the tax on Social Security checks you get?  You get a SSA-1099 for Social Security payments.

Up to 85% of Social Security 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