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Frequently Asked Questions

What is self-employment tax?

Self-employment tax (SE tax) is how self-employed individuals pay Social Security and Medicare taxes. It's 15.3% of your net self-employment income — 12.4% for Social Security and 2.9% for Medicare. When you work for an employer, you pay 7.65% and your employer pays the other 7.65%. When you're self-employed, you're both the employee and the employer, so you pay the full 15.3%.

Who needs to pay self-employment tax?

If you earn $400 or more in net self-employment income during the year, you must pay SE tax and file Schedule SE with your tax return. This includes freelancers, independent contractors, gig workers (Uber, Lyft, DoorDash, etc.), sole proprietors, and single-member LLC owners. Even if it's a side gig alongside a W-2 job, you still owe SE tax on your self-employment income.

When are quarterly estimated tax payments due?

The IRS expects self-employed individuals to pay taxes as they earn income throughout the year. Quarterly estimated payments are due on four dates:

  • Q1 (January 1 – March 31): Due April 15
  • Q2 (April 1 – May 31): Due June 15
  • Q3 (June 1 – August 31): Due September 15
  • Q4 (September 1 – December 31): Due January 15 (of the following year)

Missing these deadlines can result in underpayment penalties, even if you pay your full tax bill by April 15.

How much should I pay each quarter?

The simplest approach is the "safe harbor" rule: pay at least 100% of last year's total tax liability in equal quarterly installments (110% if your adjusted gross income exceeded $150,000). Alternatively, you can pay 90% of your current year's estimated tax liability. Our Quarterly Payment Calculator helps you estimate based on your current year-to-date income.

What deductions can I claim as a self-employed person?

You can deduct ordinary and necessary business expenses. Common deductions include: home office (simplified method: $5/sq ft up to 300 sq ft), vehicle expenses (standard mileage rate of 72.5¢/mile in 2026), health insurance premiums (100% deductible above-the-line), retirement contributions (up to 25% of net SE income for SEP-IRA), software and subscriptions, phone and internet (business-use percentage), professional development, office supplies, and advertising costs. Our Deduction Finder tool helps you identify which ones apply to you.

Is the home office deduction worth it?

The simplified home office deduction is $5 per square foot of home used for business, up to 300 square feet (maximum $1,500). It's easy to calculate and doesn't require detailed expense tracking. The regular method (actual expenses proportional to business use) may yield a larger deduction if your home expenses are high, but requires more documentation. Either way, your home must be used regularly and exclusively for business.

How do I track business mileage?

The IRS requires contemporaneous records — a log of dates, miles driven, and business purpose. You can use a notebook, spreadsheet, or an app like Stride, Everlance, or MileIQ. The standard mileage rate for 2026 is 72.5 cents per business mile. Alternatively, you can track actual vehicle expenses (gas, insurance, repairs, depreciation) and deduct the business-use percentage. Most self-employed individuals find the standard mileage rate simpler and more beneficial.

Is my data safe on this site?

Absolutely. All calculations run entirely in your web browser using JavaScript. Your income numbers, expenses, and personal information are never sent to any server, never stored in any database, and never shared with anyone. When you close the browser tab, your data is gone. We don't use cookies or tracking scripts.

How accurate are these calculators?

We use the official IRS rates and brackets for the 2026 tax year. Our SE tax calculation includes the 92.35% adjustment, the Social Security wage base limit, the additional Medicare surtax for high earners, and all seven federal tax brackets. However, individual situations vary — state taxes, tax credits, depreciation, and multiple income sources can affect your actual liability. These tools are for estimation purposes. Always consult a qualified tax professional for your specific situation.

Can I use these tools if I have both W-2 and 1099 income?

Yes. Our calculators account for W-2 income in several ways. The Social Security portion of SE tax (12.4%) only applies to income up to the wage base ($176,100 in 2026) minus any W-2 wages already subject to Social Security tax. Our calculator handles this automatically when you enter your W-2 income. The Medicare portion (2.9%) applies to all SE income regardless of other wages.