Self-Employment Tax Deductions: Complete Guide for 2025

When you're self-employed, every legitimate business expense reduces your taxable income. That means lower self-employment tax and lower income tax. Here's what you can deduct and how to document it properly.

The Big Ones: Deductions That Save Thousands

1. Home Office Deduction

If you use part of your home exclusively and regularly for business, you can deduct either $5 per square foot (simplified method, max 300 sq ft) or the actual percentage of your home expenses (mortgage/rent, utilities, insurance, repairs).

Calculate your deduction: Home Office Calculator

2. Vehicle Expenses

For 2025, the standard mileage rate is $0.70 per business mile. Track every business trip with date, destination, purpose, and mileage. Your credit card statements showing where you filled up aren't enough; the IRS wants a mileage log.

Calculate your deduction: Mileage Calculator

3. Health Insurance Premiums

If you pay for your own health insurance and aren't eligible for coverage through a spouse's plan, you can deduct 100% of premiums for yourself, your spouse, and dependents. This is an above-the-line deduction, meaning it reduces your adjusted gross income.

4. Retirement Contributions

Self-employed individuals can contribute up to $70,000 to a SEP IRA or Solo 401(k) for 2025. This reduces your taxable income dollar for dollar.

Commonly Missed Deductions

From Our Practice

The mistake we see most often: people deducting personal expenses as business expenses. A Manassas graphic designer tried to write off his family's entire cell phone plan because he "sometimes checks email on it." That doesn't work. If your phone is 30% business use, you deduct 30% of the bill.

Another common error: not keeping documentation. The IRS doesn't accept "I know I spent it, I just don't have the receipt." Your credit card statement showing a charge to Office Depot isn't enough, you need to document what you bought and why it was for business.

What You Cannot Deduct

The IRS is very clear: personal expenses are not deductible, even if you're self-employed. This includes:

How to Document Deductions

Keep your credit card statements. For larger expenses, keep invoices. For mileage, use a mileage tracking app or spreadsheet. The IRS can audit up to three years back, so keep records for at least that long.

Source: IRS Publication 535 (Business Expenses)

Verified by Nausheen Shahid — Founder, LMN Tax Inc.

22+ years in tax preparation | 5,000+ clients | Manassas, VA

Who is Nausheen?

All figures sourced from IRS.gov and verified for Tax Year 2025.