Freelancer Tax Planning Guide: Deductions, Self-Employment Tax, and S-Corp

Freelancers face a unique tax picture: unlike employees, no one withholds taxes for you, and you are responsible for both halves of payroll tax. But that same independence unlocks powerful deductions, retirement vehicles, and entity choices that employees never see. This guide covers self-employment tax, the deductions you can claim, when a Solo 401(k) or S-Corp makes sense, and how to stay current on quarterly payments — with references to the IRS rules that govern each.

Self-Employment Tax

Freelancers pay the employer and employee portions of Social Security and Medicare — a combined 15.3%:

• Social Security: 12.4% (on earnings up to the annual base, $176,100 for 2025)
• Medicare: 2.9% on all net earnings, plus a 0.9% Additional Medicare Tax above higher income thresholds

You can deduct the employer half of SE tax when computing your adjusted gross income, which softens the blow. The IRS explains this in Publication 334 (Tax Guide for Small Business) and Publication 535 (Business Expenses).

Top Deductions

1. Home office — the exclusive-use, regular-business-use portion of your home (simplified or actual method).

2. Equipment and software — computers, phones, and the tools you bill with.

3. Health insurance premiums — deductible if you are self-employed and not eligible for an employer plan.

4. Travel and mileage — business miles at the IRS standard rate; document the business purpose.

5. Retirement contributions — a Solo 401(k) allows deferrals up to $23,500 (2025) plus profit-sharing up to a total including employer contributions of about $69,000 (higher at age 50+).

6. QBI deduction — up to 20% of qualified business income under Section 199A for many pass-through owners.

Solo 401(k): A Freelancer Favorite

A Solo 401(k) lets you contribute as both employee and employer, sheltering far more than an IRA. The IRS sets the combined limit around $69,000 (2025, plus catch-up), making it the most powerful retirement tool for solo earners. You must set it up by December 31 of the tax year to contribute for that year.

S-Corp Strategy

Once net self-employment income climbs past roughly $60,000–$80,000, an S-Corporation can save real money. Instead of paying 15.3% SE tax on all profit, you pay yourself a reasonable salary (subject to payroll tax) and take the rest as distributions, which are not subject to SE tax. The IRS expects the salary to be reasonable for the role — not a token amount — so document your rationale. Elect S-Corp status with Form 2553.

Quarterly Estimated Taxes

Because nothing is withheld, you generally must pay estimated tax quarterly (April 15, June 15, September 15, January 15) if you expect to owe $1,000 or more. Underpayment can trigger penalties, so use Form 1040-ES to compute and pay on time.

A Note of Caution

Entity choice, reasonable-salary setting, and QBI thresholds involve real IRS rules. For income beyond a simple sole proprietorship, work with a CPA. The deductions are generous, but documentation is what survives an audit.

Summary

Maximize deductions, consider a Solo 401(k) early, and evaluate an S-Corp once income passes $60K–$80K. Pay quarterly taxes on time to avoid penalties. The freelancer tax code rewards those who plan and document.