Schedule C Tax Form Explained: Profit or Loss From Business, Line by Line
Quick answer
Schedule C is the tax form sole proprietors and most single-member LLC owners attach to Form 1040 to report profit or loss from a business. Gross receipts go in Part I, expenses in Part II, and the net profit flows to Schedule SE for self-employment tax and to your 1040 for income tax.
Schedule C Part II expense categories (2025 form, filed in 2026)
| Line | Deductible expense category |
|---|---|
| 8 | Advertising |
| 9 | Car and truck expenses (standard mileage rate of 70 cents per mile for 2025, or actual costs) |
| 10 | Commissions and fees |
| 11 | Contract labor (freelancers and subcontractors you paid) |
| 12 | Depletion |
| 13 | Depreciation and section 179 expense |
| 14 | Employee benefit programs |
| 15 | Insurance, other than health insurance |
| 16 | Interest on business mortgages and other business debt |
| 17 | Legal and professional services |
| 18 | Office expense |
| 19 | Pension and profit-sharing plans |
| 20 | Rent or lease of vehicles, machinery, equipment and property |
| 21 | Repairs and maintenance |
| 22 | Supplies |
| 23 | Taxes and licenses |
| 24 | Travel (24a) and deductible meals (24b) |
| 25 | Utilities |
| 26 | Wages paid to employees |
| 27 | Other expenses, itemised in Part V and carried to line 27a |
| 30 | Business use of your home (simplified method or Form 8829) |
The schedule c tax form is where American self-employment actually gets taxed. Formally "Profit or Loss From Business (Sole Proprietorship)", it attaches to Form 1040 and reduces a year of invoices and receipts to a single line: net profit or loss. Sole proprietors file it, and so does the default single-member LLC, because the IRS disregards that wrapper for income tax unless you elect corporation treatment. Statutory employees and spouses in a qualified joint venture use it too. One form per business, so two ventures means two Schedule Cs.
The flow of the form is the logic of self-employed tax. Part I collects gross receipts and returns. Part II subtracts the expense categories in the table above, which come straight from the form's own lines 8 to 27, with cost of goods sold worked out in Part III, vehicle details in Part IV, and anything uncategorised itemised in Part V. After home-office costs on line 30, the result on line 31 travels twice: to Schedule SE, where self-employment tax takes 15.3% of most of it, and to your 1040, where income tax takes its share after deductions, including the QBI deduction of up to 20% that most Schedule C filers qualify for. The table reflects the 2025 revision of the form, filed in early 2026; line numbering rarely moves, but check the current IRS instructions each January.
Because no employer withholds anything from self-employment income, Schedule C filers generally pay as they go through quarterly estimated taxes, and the profit figure also sets the ceiling on retirement contributions such as those in solo 401(k) contribution limits for 2026. The rest of our US reference shelf is at /us/guides.
This is general information for US readers, not personal tax advice. Categories and line numbers are from the IRS's 2025 Schedule C and its instructions.
Frequently asked questions
What is Schedule C on a tax form?
It is the "Profit or Loss From Business (Sole Proprietorship)" schedule that attaches to Form 1040. It turns a year of self-employment into one number: gross receipts minus business expenses equals net profit or loss, which then feeds both self-employment tax and income tax.
Who is required to file a Schedule C?
Sole proprietors, single-member LLC owners who have not elected corporation treatment, statutory employees with the box ticked on their W-2, and spouses running a qualified joint venture (each files their own). Freelance and gig income counts; no formal business registration is needed.
Is a Schedule C the same as a 1099-NEC?
No. A 1099-NEC is an information slip a client sends when it pays you $600 or more; Schedule C is the form where you report the income. All business income belongs on Schedule C whether or not anyone sent a 1099, and the expenses you deduct there are what the 1099 ignores.
What happens if I do not file Schedule C?
The IRS receives copies of your 1099s, so unreported self-employment income tends to surface as an automated notice with tax, interest and penalties calculated on the gross figure, with none of your expenses counted. If you had a loss, skipping the form also wastes a deduction you were entitled to.
What can you write off on a Schedule C?
Ordinary and necessary business expenses, which is the IRS's own test. The form itself lists the main categories on lines 8 to 27: advertising, vehicle costs, contract labor, depreciation, insurance, interest, professional fees, office costs, rent, repairs, supplies, taxes, travel, meals, utilities and wages, plus home-office costs on line 30.
Do I file Schedule C if my business made no money?
If you were actively running the business, yes. A loss on line 31 can usually be set against your other income, subject to the at-risk and hobby-loss rules. If activity genuinely stopped and there was no income or expense at all, there is nothing to report for that year.
Sources
General information, not financial advice. Tax rules and figures can change; check the current position on irs.gov or ssa.gov before acting.