Sole Trader Tax Benefits: Deductions, QBI, and Depreciation

The tax benefits of operating as a sole proprietor come down to a handful of powerful advantages: your business income is taxed only once on your personal return, you may qualify for a 20 percent deduction on qualified business income, you can write off ordinary business expenses and health insurance premiums, you can shelter large amounts in retirement plans, and you can use business losses to offset other household income. Together, these can save thousands of dollars a year.

Pass-Through Taxation on Your Personal Return

A sole proprietorship is not a separate tax entity. You report business revenue and expenses on Schedule C, and the resulting profit or loss flows directly onto your Form 1040. Your business income is taxed at your individual rates rather than at a separate corporate rate, and there is no second layer of tax when you take money out of the business. You earned it, it’s already on your return, and you keep what’s left after taxes.

For 2026, federal rates run from 10 percent on the first $12,400 of taxable income for a single filer up to 37 percent on income above $640,600. Married couples filing jointly hit the 37 percent bracket at $768,700. Before those rates apply, you subtract either the standard deduction ($16,100 single, $32,200 joint for 2026) or your itemized deductions.¹

The 20 Percent Qualified Business Income Deduction

Section 199A of the Internal Revenue Code lets sole proprietors deduct up to 20 percent of their qualified business income. If your sole proprietorship earns $100,000 in profit, you could potentially deduct $20,000 before calculating your income tax. The deduction is capped at the lesser of your combined qualified business income amount or 20 percent of taxable income minus net capital gains.²

The full deduction phases out at higher income. For 2026, it’s available in full to single filers with taxable income below roughly $201,750 and joint filers below about $403,500. Above those thresholds, limitations based on W-2 wages paid and the cost basis of depreciable property kick in, which often shrinks the deduction for sole proprietors who have no employees and minimal equipment.

Certain service fields face an extra restriction. Health care, law, accounting, consulting, financial services, and performing arts are treated as “specified service trades or businesses,” and the deduction begins to disappear entirely once income crosses the phase-in threshold. Architects and engineers are specifically excluded from that restriction and keep access to the full deduction regardless of income.²

Ordinary and Necessary Business Expenses

Every dollar you spend that qualifies as “ordinary and necessary” reduces your taxable profit. Section 162 of the Internal Revenue Code allows deductions for reasonable employee compensation, travel while away from home on business, rent for property used in your trade, and similar costs.³ “Ordinary” means common in your line of work. “Necessary” means helpful and appropriate, not that you’d go out of business without it.

Typical write-offs include supplies and materials, software subscriptions, advertising, professional services like bookkeeping, business insurance, and shipping. Travel to meet clients or attend industry events qualifies. Your daily commute to a regular office does not. Costs that mix personal and business use, like a phone you use for both, need to be split so you only deduct the business portion.

These deductions come out on Schedule C before your adjusted gross income is calculated. A lower AGI can then unlock or preserve eligibility for other tax benefits that phase out at higher income levels.

Home Office Deduction

If you use part of your home exclusively and regularly as your principal place of business, you can deduct a portion of your housing costs. The space has to be used only for business. A kitchen table where you also eat dinner does not qualify. A dedicated room or partitioned area used solely for work does.⁴

The IRS offers two calculation methods. Under the simplified method, you deduct $5 per square foot of office space, up to 300 square feet, for a maximum of $1,500. No depreciation calculations, no tracking utility bills. Under the regular method, you total your actual home expenses (mortgage interest or rent, utilities, insurance, repairs, depreciation) and allocate a percentage to the office based on its share of your total floor space. The regular method takes more record-keeping but often yields a larger deduction, especially if your office is a significant portion of your home.⁴

The exclusive use requirement has a few exceptions. If you store inventory at home and your home is the business’s only fixed location, the storage area doesn’t need to be used exclusively for business. A separate detached structure, like a garage converted into a workshop, also qualifies as long as you use it regularly for the business.⁵

Vehicle Expenses

When you drive for business, you can deduct either the standard mileage rate or your actual vehicle expenses, but not both. For 2026, the standard mileage rate is 72.5 cents per mile.⁶ That rate covers depreciation, insurance, gas, repairs, and maintenance in a single per-mile figure.

The actual expense method works better for some sole proprietors, particularly those with higher-cost vehicles or heavy business use. You track every dollar spent on gas, oil changes, tires, insurance, registration, loan interest, and depreciation, then multiply by the percentage of miles driven for business. Whichever method you choose, you need a contemporaneous log of business miles: date, destination, business purpose, and mileage. Without that log, the deduction falls apart during an audit faster than almost any other claim.

Section 179 and Bonus Depreciation on Equipment

When you buy equipment, furniture, or other tangible property for your business, you’d normally depreciate the cost over several years. Section 179 lets you deduct the full purchase price in the year you place the asset in service. The base statutory limit is $2,500,000, with inflation adjustments beginning in tax years after 2025.⁷ For 2026, the inflation-adjusted limit is approximately $2,560,000, and the deduction begins phasing out when total equipment purchases exceed roughly $4,090,000.

Watch one limitation: your Section 179 deduction cannot exceed your taxable income from the active conduct of your trade or business. If your Schedule C shows $40,000 in profit and you bought $50,000 in equipment, you can only expense $40,000 under Section 179. The remaining $10,000 carries forward.⁷

Bonus depreciation offers a separate path for first-year write-offs and has been phasing down since 2023. For property placed in service during 2026, the bonus rate is 20 percent.⁸ Unlike Section 179, bonus depreciation isn’t limited by business income and can create or increase a net loss. For most sole proprietors buying moderate amounts of equipment, Section 179 is the more practical tool.

Self-Employed Health Insurance Deduction

One of the most overlooked benefits is the ability to deduct health insurance premiums as an above-the-line adjustment to income. Premiums for medical, dental, or long-term care coverage for yourself, your spouse, or your dependents come straight off your gross income before tax is calculated.⁹

The deduction cannot exceed your net self-employment income for the year, and you cannot claim it for any month in which you were eligible to participate in an employer-subsidized health plan, including a spouse’s employer plan. If you receive a premium tax credit through a marketplace plan, the deduction is reduced by the credit amount. Even with those guardrails, this deduction can save a sole proprietor $2,000 to $5,000 a year, depending on coverage cost and tax bracket.

Retirement Plan Contributions

Sole proprietors have access to retirement plans that shelter substantial amounts of income from current-year taxes. The two most common are SEP IRAs and solo 401(k) plans.

SEP IRA

A Simplified Employee Pension IRA lets you contribute up to 25 percent of your net self-employment earnings, with a 2026 maximum of $72,000.¹⁰ Setup is minimal, there are no annual IRS filing requirements until balances reach certain thresholds, and you can vary contributions from year to year or skip a year entirely. The trade-off: all contributions are employer contributions, so there is no employee elective deferral component.

Solo 401(k)

A solo 401(k) gives you two contribution buckets. You can defer up to $23,500 as the “employee” side in 2026, then add employer profit-sharing contributions of up to 25 percent of net self-employment earnings. The combined total cannot exceed $72,000, or $80,000 if you’re 50 or older. Individuals aged 60 through 63 get a higher catch-up allowance, pushing the combined ceiling to $83,250.¹¹

Both plans reduce your taxable income dollar-for-dollar in the year you contribute, and investments grow tax-deferred until retirement. The solo 401(k) tends to be the better choice when your net income is below roughly $290,000, because the employee deferral component lets you shelter more at lower income levels than the SEP’s percentage-only formula allows.

Deducting Half of Your Self-Employment Tax

Self-employment tax is the sole proprietor’s version of the Social Security and Medicare payroll taxes that employers and employees normally split. Because you are both, you pay the full 15.3 percent: 12.4 percent for Social Security and 2.9 percent for Medicare.¹² For 2026, the Social Security portion applies only to the first $184,500 of net self-employment earnings. Medicare has no cap.¹³

The benefit is that you can deduct half of your self-employment tax as an adjustment to gross income on Form 1040. This deduction doesn’t reduce the self-employment tax itself, but it lowers the income on which you calculate regular income tax.¹² On $100,000 of net self-employment income, you’d owe roughly $14,130 in self-employment tax and get to subtract about $7,065 from your AGI. At a 22 percent marginal rate, that saves about $1,554 in income tax.

If your net self-employment income exceeds $200,000 as a single filer or $250,000 on a joint return, you also owe an Additional Medicare Tax of 0.9 percent on earnings above those thresholds. That additional tax has no corresponding deduction.¹⁴

Using Business Losses to Offset Other Income

When your Schedule C shows a net loss, that loss flows directly to Form 1040 and offsets your other income: wages from a day job, investment income, a spouse’s earnings on a joint return. This is a structural advantage of the sole proprietorship. In a C corporation, losses stay trapped inside the business entity. In a sole proprietorship, a business loss immediately reduces the household tax bill.

There is a ceiling. The excess business loss limitation prevents noncorporate taxpayers from using business losses above a threshold to offset nonbusiness income. For 2026, that threshold is $256,000 for single filers and $512,000 for joint filers. Any loss beyond the limit doesn’t disappear; it converts into a net operating loss that carries forward. This mainly affects high-income sole proprietors with large first-year losses, not someone whose consulting business lost $15,000 during its launch year.

Losses need to be legitimate. If your business shows a loss year after year without a realistic prospect of profit, the IRS may reclassify the activity as a hobby, which eliminates your ability to deduct losses against other income. The general guideline is that a business should show a profit in at least three out of every five consecutive years, though that’s a presumption rather than an absolute rule.

The Flip Side: Quarterly Estimated Payments

These benefits come with one obligation worth knowing before you count on them. Because no employer withholds taxes from your sole proprietor income, you’re responsible for sending the IRS quarterly estimated payments. If you expect to owe $1,000 or more when you file (after withholding and credits), you need to make these payments or face an underpayment penalty.¹⁵

The 2026 quarterly deadlines are April 15, 2026; June 15, 2026; September 15, 2026; and January 15, 2027. You can avoid the underpayment penalty by paying at least 90 percent of your current-year tax liability during the year, or by paying 100 percent of your prior-year tax liability (110 percent if your prior-year AGI exceeded $150,000).¹⁵ The prior-year safe harbor is the easier target when current-year income is hard to predict. Many sole proprietors divide last year’s total tax by four, send that amount each quarter, and settle up at filing.

1
Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
2
Office of the Law Revision Counsel. 26 USC 199A – Qualified Business Income
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Office of the Law Revision Counsel. 26 USC 162 – Trade or Business Expenses
4
Internal Revenue Service. Topic No. 509, Business Use of Home
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Office of the Law Revision Counsel. 26 USC 280A – Disallowance of Certain Expenses in Connection With Business Use of Home
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Internal Revenue Service. The Standard Mileage Rates and Maximum Automobile Fair Market Values Have Been Updated for 2026
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Office of the Law Revision Counsel. 26 USC 179 – Election to Expense Certain Depreciable Business Assets
8
Internal Revenue Service. Revenue Procedure 2026-15
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eCFR. 26 CFR 1.162(l)-1 – Deduction for Health Insurance Costs of Self-Employed Individuals
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Internal Revenue Service. SEP Contribution Limits (Including Grandfathered SARSEPs)
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Internal Revenue Service. Retirement Topics – 401(k) and Profit-Sharing Plan Contribution Limits
12
Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes)
13
Social Security Administration. Contribution and Benefit Base
14
Internal Revenue Service. Questions and Answers for the Additional Medicare Tax
15
Internal Revenue Service. Estimated Taxes