Self-employment tax guide for 2025-2027
Self-employment tax covers Social Security and Medicare on net earnings. Use this guide to estimate 2025-2027 SECA tax, plan quarterly payments, and track deductions like mileage or home office to reduce taxable income.
What counts as self-employment income
- Net profit from 1099 work, freelancing, or a sole proprietorship.
- Business income reported on Schedule C.
Estimate quarterly payments
- Estimate annual profit and SE tax.
- Use safe harbor guidelines to avoid penalties.
- Divide annual liability into quarterly payments.
Common deductions to track
- Home office and business mileage.
- Supplies, software, and professional services.
- Health insurance and retirement contributions (if eligible).
Put this tax guide into practice
Identify the tax year, filing status, income type, and household or business facts that apply before comparing options. Keep the source documents behind each number and use the linked calculator for a repeatable estimate. Changing one assumption at a time makes it easier to see which rule drives the result.
Review the calculator's assumptions, caveats, update date, and primary source links before acting. A guide can explain the planning framework, but official forms and instructions control a filed return. Seek qualified advice for notices, amended returns, multiple jurisdictions, business entities, or material transactions.
Save the assumptions used with the estimate and revisit them after an official annual adjustment or a change in income, residency, household, employment, or investment plans. Consistent inputs make comparisons meaningful.
Related calculators
Self-employment tax estimator (SECA)
Estimate SECA tax on net earnings.
1099 tax estimator
Estimate total tax on 1099 income.
Quarterly estimated payments planner
Plan quarterly payments based on income.
Home office deduction estimator
Estimate allowable home office deductions.
Mileage deduction calculator
Estimate vehicle mileage deductions.
Set-aside % rule-of-thumb calculator
Decide how much income to set aside for taxes.
FAQ
Do I owe self-employment tax if I have a W-2 job too?
Yes. Self-employment tax applies to net earnings from self-employment in addition to any W-2 wages.
Updated 2026-01-20. TaxGuide Pro provides educational tax guidance, not legal advice.