You pay Self Employment tax on $400 or more of net profit from self-employment in addition to any regular income tax on it. You pay 15.3% SE tax on 92.35% of your Net Profit greater than $400. The 15.3% self employed SE Tax is to pay both the employer part and employee part of Social Security and Medicare. So you get social security credit for it when you retire.
PAYING ESTIMATES
You may need to send in quarterly estimated payments to cover any self employment tax and increase in income.
You must make quarterly estimated tax payments for the current tax year if both of the following apply:
- 1. You expect to owe at least $1,000 in tax for the current tax year, after subtracting your withholding and credits.
- 2. You expect your withholding and credits to be less than the smaller of:
90% of the tax to be shown on your current year’s tax return, or
100% of the tax shown on your prior year’s tax return. (Your prior year tax return must cover all 12 months).
Turbo Tax will calculate the 1040ES estimated payments
https://ttlc.intuit.com/community/tax-payments/help/can-turbotax-calculate-next-year-s-federal-estim...
How to make the Estimated payments
https://ttlc.intuit.com/community/tax-payments/help/how-do-i-make-estimated-tax-payments/00/25875
Here are the blank Estimates and instructions…..
http://www.irs.gov/pub/irs-pdf/f1040es.pdf
