Generally speaking, it works like this. Your total income is subject to INCOME tax and this includes your self-employment income...the $10,000 you mentioned. Your SS income is partially taxable once your income exceeds $25k, based on your total income from all sources.
Additionally, your self-employment NET income is also subject to 15.3% social security tax. Net income is your gross income ($10,000) less your business expenses. So keep track of those business expenses and they will help you reduce your total taxes.
Good luck to you.
Kelly C, CPA
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