Self-Employment Tax and the QBI Deduction in 2026

If you work for yourself — whether as a freelancer, a sole proprietor, or an owner of an LLC taxed as a partnership — you owe two layers of federal tax that an ordinary employee does not. This guide covers both, how the qualified business income deduction can offset some of the pain, and the planning moves that actually reduce your bill. (Internal Revenue Service)

The two layers you owe

Self-employment tax is the Social Security and Medicare contribution that employees pay through payroll withholding. Because you are both employer and employee, you owe the full amount rather than just the employee half. The self-employment tax rate for 2026 is 15.3%, split between Social Security (12.4%) and Medicare (2.9%). (Internal Revenue Service)

Two important limits apply. The Social Security portion caps off at the annual wage base, which in recent years has been around $160,000 to $170,000 — only earnings up to that threshold are taxed for Social Security. The Medicare portion has no cap, and a 2% surcharge applies to earnings above a high-income threshold. (Internal Revenue Service)

A subtle but important detail: you report self-employment tax on 92.35% of your net profit, not 100%. You can deduct half of your self-employment tax on your income tax return as an adjustment to income, which lowers your taxable income from that line. (Internal Revenue Service)

The QBI deduction

For many sole proprietors and single-member LLCs, the qualified business income deduction is one of the most valuable individual tax breaks in the code. It allows you to deduct up to 20% of your qualified business income, reducing your ordinary federal tax at your marginal rate. (Internal Revenue Service)

The deduction has limits that depend on your taxable income. Below the threshold amount (which the IRS adjusts annually, around $190,000 for single filers and $390,000 for joint filers in recent years), the deduction is simply 20% of QBI with no other constraints. Above that threshold, the deduction is capped at the greater of 20% of wages paid by the business or 2.5% of the adjusted basis of qualified property held by the business. (Internal Revenue Service)

Service businesses — including consulting, healthcare, law, accounting, financial services, and most similar professions — lose the deduction entirely once taxable income exceeds the phase-out range above the threshold. This is where many high-earning professionals lose the most value, and it is worth checking whether your specific line of work qualifies before you plan around the deduction. (Internal Revenue Service)

Planning moves that help

Contribute to a Solo 401(k) or SEP-IRA to lower taxable income before QBI is computed. Accelerate deductible expenses into the year where you expect QBI to be highest. If you are a partner in a partnership, negotiate a wage allocation to keep the QBI wage-based cap from binding. And if you are a small business, consider whether converting your entity type changes the QBI math. (Internal Revenue Service)

Estimating your self-employment tax

A quick way to estimate your annual self-employment tax: take your expected net profit, multiply by 92.35%, then apply the Social Security rate to the portion below the wage base and the Medicare rate to all of it. The half deduction saves you additional ordinary income tax, but that is a benefit you recognize when you run your income tax return, not when you set aside for self-employment tax. (Internal Revenue Service)

What this means for you

Self-employment tax is one of the most underrated tax items in the code. A solo practitioner earning $150,000 in net profit owes roughly $22,000 in self-employment tax before any QBI savings, and the QBI deduction can recover maybe $6,000 to $10,000 of that depending on income and industry. Budgeting for the full amount upfront — and not just the income tax — is the difference between a smooth cash-flow year and an April surprise. (Internal Revenue Service)

How self-employment tax differs by filing status

The two layers of tax interact differently depending on how you file. A single filer with no other income pays self-employment tax on the full net profit after the 92.35% adjustment. A married couple where one spouse is self-employed and the other is a W-2 employee still pays self-employment tax only on the self-employment income — the wages do not stack. But the household's combined income drives the QBI threshold, so a high W-2 salary can push the household over the QBI limit even when the self-employment income alone would not have crossed it. (Internal Revenue Service)

Quarterly estimated payments

Self-employment income has no employer withholding, so you owe estimated payments four times a year. Under-estimating can trigger an accuracy penalty of 0.5% to 1% per month of underpayment. The safe harbor is paying at least 90% of the current year's tax or 100% of last year's paid tax (110% if your AGI was above the high-income threshold). Many self-employed people set up automatic quarterly contributions to a tax account and withdraw from there when a quarter comes due — the cost of an overdraft or a late-payment penalty far exceeds the interest they earn in a money-market account. (Internal Revenue Service)

The state layer

Most states tax self-employment income the same way they tax wages, though some, like California and Washington, layer their own levies on top of the federal self-employment tax. Washington, for instance, has a separate capital gains tax and a WA Cares payroll premium that touches certain self-employed workers. If you work across state lines, your state of residence may also tax the self-employment income even if the work is performed elsewhere — residency drives self-employment tax jurisdiction in most states. (Internal Revenue Service)

What changes in 2026

The qualified business income deduction, scheduled to sunset at the end of 2025, may be extended or modified depending on the legislation in force for 2026. The QBI deduction is the single biggest deduction available to a solo practitioner above the standard deduction, so its status is worth tracking in the second half of the year. If it does sunset, a high-income service professional sees the deduction disappear on January 1, 2026, which is a dramatic swing. (Internal Revenue Service)

Disclaimer: This article is general educational information, not tax, legal, or investment advice. Dollar amounts come from the 2026 sources listed at the end of this article and may change. Before you act, talk to a licensed CPA, EA, or tax attorney about your own situation.