Reviewed August 27, 2026
How the side hustle tax estimate works
This calculator is a planning worksheet, not tax-preparation software. It separates net business profit, federal income-tax assumptions, self-employment tax, state estimates, credits, withholding, and quarterly-payment planning so users can see what moves the result.
Calculation standard
- Business expenses are subtracted from gross side-hustle income before estimating taxes.
- Self-employment tax is estimated separately from federal income tax; the two are not interchangeable.
- Entered W-2 withholding and credits reduce the projected balance, not the underlying side-hustle profit.
- State estimates are simplified planning rates and must be checked against the user's resident and work states.
Primary IRS references
- IRS self-employment tax — Definition, Schedule SE context, and the employer-equivalent deduction.
- IRS estimated taxes — Who may need estimated payments and the general $1,000 expected-balance threshold for individuals.
- 2026 Form 1040-ES — Current-year worksheet and payment instructions.
- IRS gig economy tax center — Reporting and recordkeeping context for platform and freelance income.
Freshness and limitations
Federal assumptions, displayed dates, calculator logic, and source links were reviewed August 27, 2026. Tax law and IRS guidance can change. Confirm the current Form 1040-ES instructions and your state rules before paying or filing. Complex filing status, multiple businesses, entity elections, credits, depreciation, and local tax can require professional review.
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