Add up your net earnings from self-employment
Multiply net earnings by 92.35% to get the taxable amount
Multiply the taxable amount by 15.3% to estimate self-employment tax
Use 12.4% for Social Security tax on earnings up to the annual wage base limit
Use 2.9% for Medicare tax on all taxable self-employment earnings
Add the Social Security and Medicare amounts together
Add 0.9% Additional Medicare Tax if your earnings exceed the IRS threshold
Subtract one-half of your self-employment tax when calculating adjusted gross income
Use Schedule SE to calculate the exact tax amount
Include the self-employment tax on your federal tax return
Make estimated quarterly tax payments if required