CalcWolf Finance Side Hustle Tax Withholding Calculator
Finance

Side Hustle & Freelance Tax Estimator

How much to set aside from every side hustle payment for taxes.

📅 Updated April 2026 Formula verified 📖 4 min read 🆓 Free · No sign-up

Self-employment tax: the big surprise

As a freelancer you pay both the employee AND employer share of Social Security and Medicare — 15.3% on top of income tax. On $20,000 of side income, self-employment tax alone is ~$2,826. Many new freelancers miss this and face a painful tax bill.

Quarterly estimated taxes

Pay quarterly or face underpayment penalties. 2026 due dates: April 15, June 16, September 15, January 15. Each payment = ~25% of your estimated annual tax.

Don't forget these deductions

  • Home office (dedicated space)
  • Software and subscriptions
  • Phone and internet (business %)
  • Health insurance premiums
⚡ CalcWolf Insight

The average freelancer underpays taxes by $2,800 in their first year. Setting aside 25–30% of every side hustle payment avoids the most common new freelancer mistake.

Frequently asked questions
How much tax do I owe on side hustle income?
Typically 25–35% total: 15.3% self-employment tax + your marginal income tax rate on the net profit. Set aside 30% of every payment to be safe.
✓ Math logic verified against primary sources → See our verification process
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Founder, CalcWolf · GLVTS · Blickr
All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →
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