According to SECA, self-employed individuals are required to pay the entire 15.3% of FICA taxes. This total is also called self-employment tax, and it has two parts: Social Security tax and Medicare tax.
12.4% of your SECA tax goes toward Social Security, but there is a limit to that. The amount changes every year, but after a certain amount of income, you no longer have to pay Social Security tax. In the 2023 tax year, the limit was $160,200. Anything over that amount won't be taxed.
If you made $200,000 in net earnings in 2023 from your
online business selling handmade gifts, for example, you will owe 12.4% tax on the first $160,200 of it. But you wouldn't be required to pay any Social Security tax on the last $39,800, but you will need to make
estimated tax payments.
The second 2.9% of the FICA taxes that self-employed people owe goes to fund Medicare, but there is no limit to this part. You will need to pay 2.9% on the full $160,000 you earned with your online business. If you need help figuring out how much you might owe, consider using a
1099 tax calculator.