If you work as a 1099 contractor, you pay two federal taxes on your net business profit: self-employment tax at a combined 15.3% and regular federal income tax at rates from 10% to 37%. On top of that, most states charge their own income tax. Because no one withholds anything from your pay, you calculate and send the money yourself, usually in four quarterly installments.
That’s the short answer. The rest of this article walks through each piece, the deductions that reduce what you owe, and how to keep the IRS off your back with on-time payments.
Self-Employment Tax
Self-employment tax is the one that surprises people. It funds Social Security and Medicare, and it exists because you don’t have an employer splitting those contributions with you. The combined rate is 15.3%: 12.4% for Social Security and 2.9% for Medicare.1Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes) In a W-2 job, your employer covers half. As a contractor, you cover both sides. It kicks in once your net earnings from self-employment reach $400 for the year.
The rate doesn’t apply to your entire net profit. It applies to 92.35% of it.2Internal Revenue Service. Topic No. 554, Self-Employment Tax The adjustment reflects the fact that W-2 employees don’t pay FICA on the employer’s share of payroll tax. So if your Schedule C shows $100,000 in net profit, self-employment tax is calculated on $92,350, saving you roughly $1,200 versus the full amount.
The Social Security portion (12.4%) only applies up to the annual wage base, which is $184,500 for 2026.3Social Security Administration. Maximum Taxable Earnings Above that cap, the Social Security piece stops. The 2.9% Medicare piece never does. Higher earners also owe an additional 0.9% Medicare surcharge on self-employment income above $200,000 for single filers, $250,000 for married filing jointly, or $125,000 for married filing separately.4Internal Revenue Service. Topic No. 560, Additional Medicare Tax
One partial offset: you can deduct roughly half of your self-employment tax (the employer-equivalent portion) when calculating your adjusted gross income.1Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes) It’s an above-the-line deduction, so you get it whether or not you itemize. It doesn’t cut your self-employment tax itself, but it lowers the income figure your federal income tax runs against.
Federal Income Tax
Federal income tax stacks on top of self-employment tax. The two don’t overlap and don’t cancel out. You pay both, separately, on the same net profit.
Federal rates are progressive. Only the income inside each bracket is taxed at that bracket’s rate. For 2026, single filers pay 10% on the first $12,400 of taxable income and reach the top 37% bracket above $640,600. Married couples filing jointly hit the 37% bracket above $768,700. The 2026 standard deduction is $16,100 for single filers, $32,200 for married filing jointly, and $24,150 for head of household.5Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
A rough example: a sole proprietor with $80,000 in net profit might owe about $11,300 in self-employment tax plus several thousand more in federal income tax, depending on filing status and deductions.
The 20% Qualified Business Income Deduction
Section 199A lets eligible self-employed individuals deduct up to 20% of their qualified business income before calculating federal income tax.6Internal Revenue Service. Qualified Business Income Deduction The One Big Beautiful Bill Act made this deduction permanent after it was originally set to expire at the end of 2025. For a contractor with $80,000 in qualified business income, the deduction removes $16,000 from the taxable income calculation.
Below certain income thresholds, you take the full 20% without limitation. Above those thresholds, the deduction phases out, and the phase-out is stricter for specified service trades like law, accounting, health care, and consulting. The thresholds adjust annually for inflation. The deduction only lowers income tax, not self-employment tax, but it’s one of the most valuable breaks a sole proprietor gets.
Deductions That Lower Both Taxes
Every legitimate business expense you deduct reduces your net profit, and net profit is what both self-employment tax and income tax are calculated on. That makes deductions worth more to a contractor than to a W-2 employee.
Home Office
If you use part of your home regularly and exclusively for business, you can deduct a portion of your housing costs. The simplified method gives you $5 per square foot of dedicated office space, capped at 300 square feet and $1,500 total.7Internal Revenue Service. Simplified Option for Home Office Deduction The regular method calculates the business-use percentage of actual expenses like rent, utilities, and insurance. It takes more record-keeping but usually produces a bigger deduction, especially in expensive housing markets.
Business Mileage
Driving to meet clients, reach job sites, or pick up supplies qualifies at the IRS standard mileage rate of 72.5 cents per mile for 2026.8Internal Revenue Service. 2026 Standard Mileage Rates Fifteen thousand business miles works out to a $10,875 deduction. You can instead track actual vehicle expenses like gas, insurance, and depreciation, but the standard rate is simpler and often close. Either way, keep a log showing date, destination, business purpose, and miles.
Self-Employed Health Insurance
You can deduct 100% of health, dental, and vision premiums paid for yourself, your spouse, and your dependents. The plan has to be established under your business, and you can’t claim the deduction for any month you were eligible for a subsidized employer plan through a spouse or another source.9Internal Revenue Service. Instructions for Form 7206 This one is above the line, so no itemizing required. A family paying $1,200 a month in premiums gets a $14,400 deduction.
Meals and Other Ordinary Expenses
Business meals with clients or while traveling for work are deductible at 50%.10Internal Revenue Service. Topic No. 511, Business Travel Expenses Software subscriptions, professional development, office supplies, business insurance, and similar ordinary and necessary costs are fully deductible. Everything flows through Schedule C.
Quarterly Estimated Payments
Federal tax is pay-as-you-go, so you can’t wait until April. Contractors send four estimated payments covering both income tax and self-employment tax:
- April 15 for income earned January through March
- June 15 for income earned April through May
- September 15 for income earned June through August
- January 15 of the following year for income earned September through December
Dates shift to the next business day when they fall on a weekend or holiday.11Internal Revenue Service. Pay As You Go, So You Won’t Owe
IRS Direct Pay transfers funds from your bank account for free without requiring an account.12Internal Revenue Service. Direct Pay With Bank Account The Electronic Federal Tax Payment System (EFTPS) needs enrollment but offers better tracking. You can also mail Form 1040-ES with a check.13Internal Revenue Service. Estimated Taxes If you overpay one year, you can roll the refund into next year’s first estimated payment.
How to Avoid Underpayment Penalties
If you miss a quarterly payment or send too little, the IRS charges interest at the underpayment rate (7% annually for 2026), running from each missed due date until the money arrives.14Internal Revenue Service. Quarterly Interest Rates15Office of the Law Revision Counsel. 26 USC 6654 The penalty is usually small in absolute dollars, but it’s fully avoidable if you land inside one of the safe harbors:
- Under $1,000 owed. If your total tax minus withholding and credits is less than $1,000, no penalty.
- 90% of the current year. Your payments and withholding covered at least 90% of what you actually owe for the year.
- 100% of last year’s tax. Your payments matched or exceeded the total tax on your prior-year return. If your prior-year adjusted gross income was above $150,000 ($75,000 if married filing separately), the threshold rises to 110%.
The prior-year safe harbor is the practical one for most contractors.16Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty If your income swings from year to year, basing your quarterly payments on last year’s total tax gives you a fixed number to divide into four installments. You may still owe a balance in April, but not a penalty on top of it.
Forms You Actually File
Clients who pay you $600 or more during the year are supposed to send you a Form 1099-NEC reporting the total.17Internal Revenue Service. Instructions for Forms 1099-MISC and 1099-NEC You owe tax on all your self-employment income regardless of whether a 1099 shows up. If a client pays you $500, no 1099 is required, but the income is still reportable. The IRS treats 1099s as an information tool, not as the trigger for your tax obligation.
Your return itself has three connected pieces. Schedule C (Form 1040) is where you report gross business income, subtract expenses, and land on net profit.18Internal Revenue Service. 2025 Instructions for Schedule C (Form 1040) That net profit flows to Schedule SE, which calculates self-employment tax.19Internal Revenue Service. 1099-MISC, Independent Contractors, and Self-Employed Both attach to your Form 1040. Keep receipts, bank statements, mileage logs, and copies of your 1099s throughout the year. Reconstructing them in April is painful and usually incomplete.
State and Local Taxes
Federal taxes are only part of what you owe. Most states impose their own income tax on self-employment earnings, with rates and structures that vary. Some use a flat rate, others have progressive brackets. A handful of states, including Texas, Florida, and Nevada, have no individual income tax at all.
Some cities and counties add their own income taxes, collected separately from federal and state. The percentages tend to be modest but are easy to miss, especially after a move or when you work across multiple jurisdictions. Check with your state tax agency early, because the quarterly payment discipline that applies federally usually applies to state estimated taxes too.