No. You only pay SS & Medicare tax on W2 wages or a net profit on self employment. Although if you receive Social Security benefits it may be taxable. Also if you have a lot of investment income there may be a NIT tax. The net investment income tax (NIIT) is a 3.8% tax on investment income such as capital gains, dividends, and rental property income. This tax only applies to high-income taxpayers, such as single filers who make more than $200,000 and married couples who make more than $250,000, as well as certain estates and trusts. The NIIT is on Schedule 2 line 12 and goes to 1040 line 23 Other Taxes.
No matter what age.......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
And if you start getting SS before the full retirement age, they will reduce your payments if you make too much other income in the prior year. See SS FAQ for working after retirement
https://www.ssa.gov/benefits/retirement/planner/whileworking.html
