Business net profit is what your company keeps after every cost has been subtracted from revenue: cost of goods sold, operating expenses, interest on debt, and taxes. It is the last line on the income statement, which is why people call it the bottom line. That single figure tells you whether the business made money or lost it during the period, and a version of it is what the IRS uses to calculate the tax you owe.
The Formula
The calculation runs in a fixed order, and each subtraction narrows the picture:
- Total revenue, minus
- Cost of goods sold (COGS), equals gross profit
- Minus operating expenses, equals operating profit
- Minus interest paid on business debt
- Minus taxes, equals net profit
If the last number is negative, you have a net loss. That is not automatically a crisis, but expenses outpaced revenue and the tax code treats the shortfall differently from a profit. More on that below.
Revenue and COGS
Revenue is every dollar the business earned from its main activities in the period: product sales, service fees, subscription income. It sits at the top of the income statement, before anything is taken out.
Cost of goods sold covers the direct costs of producing what you sold. A manufacturer’s COGS is raw materials and production labor. A retailer’s is the wholesale cost of inventory. A service business with little physical product may have almost no COGS at all. The numbers live in supplier invoices, purchase orders, and inventory records. Revenue minus COGS is gross profit, which measures how efficiently you turn inputs into sellable output before overhead enters the picture.
Operating Expenses
Operating expenses are the costs of running the business that are not tied to producing a specific unit of what you sell. Rent, utilities, payroll for administrative and sales staff, insurance, workers’ compensation coverage, software subscriptions. They show up on your general ledger and bank statements. Miss a recurring expense and your net profit on paper is overstated.
Depreciation and Amortization
Depreciation is the operating expense most owners get wrong, and it can move your net profit meaningfully. When you buy equipment, a vehicle, or office furniture, you generally can’t deduct the full purchase in the year of purchase. You spread the cost over the asset’s useful life using the IRS’s Modified Accelerated Cost Recovery System (MACRS). Under MACRS, computers and vehicles are typically written off over five years, and office furniture over seven.1Internal Revenue Service. Publication 946, How To Depreciate Property
Two provisions let you pull that deduction forward. A Section 179 election lets you deduct the full purchase price of qualifying equipment in the year it is placed in service, up to $2,560,000 for tax year 2026. Bonus depreciation was restored to 100% for qualified property acquired and placed in service after January 19, 2025, and is now permanent. Both approaches front-load the tax benefit, which lowers taxable income now and leaves less depreciation to claim later.
Interest on Business Debt
After operating expenses, subtract interest paid on any business borrowing: bank loans, SBA loans, equipment financing, business credit lines. SBA 7(a) loans, for example, carry variable rates capped at prime plus a spread tied to loan size.2U.S. Small Business Administration. 7(a) Loan Program Terms, Conditions, and Eligibility Interest reduces net profit, but it also reduces taxable income, so capturing every payment accurately matters on both sides.
Net Profit on the Income Statement
The income statement, also called a profit and loss statement or P&L, is where these figures come together in the order above. Revenue at the top, expenses in sequence, net profit at the bottom. Anyone reading a P&L can jump straight to the last line and know whether the period was profitable.
Even small private businesses benefit from following the standard layout. Banks expect it before extending a loan, buyers expect it in due diligence, and comparing your results to industry benchmarks is only meaningful when the numbers are organized the same way.
Net Profit Margin
The raw number is more useful as a percentage of revenue: (Net Profit ÷ Revenue) × 100. That is your net profit margin, and it lets you compare against businesses of different sizes. Averages swing hard by industry. Software companies commonly clear 14%. Grocery retailers run closer to 2%. A 5% margin looks thin in isolation but strong against a 3% industry average.
Net Profit Is Not Cash
A profitable P&L does not guarantee money in the bank. Under accrual accounting, revenue is recorded when a sale is made, not when the customer pays. A business can show a healthy net profit and still miss payroll because $80,000 in invoices are outstanding. The reverse happens too: collecting on old receivables brings in cash that doesn’t register as new income on the current statement.
Depreciation adds another gap. It reduces net profit but no cash actually leaves the account, so a business with heavy depreciation deductions can show modest profit with substantially more cash on hand. The cash flow statement reconciles these timing differences. Don’t make spending decisions from net profit alone.
How Net Profit Becomes Your Tax Bill
Net profit is the starting point for calculating tax, but it is not always the same as taxable income. The Internal Revenue Code requires adjustments that may differ from how you tracked expenses on your books. Business meals are the classic example: you likely deducted the full cost against accounting profit, but the IRS allows only a 50% deduction for most business meals.3Internal Revenue Service. Topic No. 511 Business Travel Expenses Book profit and taxable income rarely match exactly.
C-Corporations
C-corporations pay a flat 21% federal tax on taxable income.4Internal Revenue Service. Publication 542 – Corporations The tax is paid at the corporate level, and when profits are distributed as dividends the shareholders pay tax again on the distribution. That double layer is the main reason many small businesses choose a different structure.
A C-corp that holds too much profit inside the company rather than distributing or reinvesting it can also face a 20% accumulated earnings tax on the excess.5Office of the Law Revision Counsel. 26 USC 531 – Imposition of Accumulated Earnings Tax A credit typically shields the first $250,000 of accumulated earnings.6Office of the Law Revision Counsel. 26 USC 535 – Accumulated Taxable Income
Pass-Through Entities
S-corporations, partnerships, LLCs taxed as partnerships, and sole proprietorships pay no federal income tax at the business level. Net profit passes through to the owners, who report their share on personal returns. For 2026, individual federal rates run from 10% to 37% depending on total taxable income and filing status.7Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
Pass-through owners may also qualify for the Qualified Business Income deduction, worth up to 20% of qualified business income against taxable income.8Internal Revenue Service. Qualified Business Income Deduction The deduction had been scheduled to expire after 2025, but the One Big Beautiful Bill Act, signed on July 4, 2025, made it permanent. Income earned through a C-corp or as a W-2 employee does not qualify. At higher income levels the deduction phases out for owners of specified service businesses like law, accounting, and consulting.
Self-Employment Tax
Sole proprietors and general partners owe self-employment tax on net profit in addition to income tax. The combined rate is 15.3%: 12.4% for Social Security and 2.9% for Medicare.9Internal Revenue Service. Self-Employment Tax (Social Security and Medicare Taxes) The Social Security portion applies only to the first $184,500 of net earnings in 2026.10Social Security Administration. 2026 Cost-of-Living Adjustment (COLA) Fact Sheet Earnings above $200,000 for single filers, or $250,000 for joint filers, trigger an additional 0.9% Medicare surtax.
You can deduct half the self-employment tax (the employer-equivalent portion) when calculating adjusted gross income. That deduction reduces income tax but not the self-employment tax itself. S-corporation owners who pay themselves a reasonable salary can limit self-employment tax exposure, because only wages are subject to payroll tax, not distributions. That is one of the most common reasons profitable businesses elect S-corp status.
State Taxes
Federal is not the whole bill. Most states impose their own corporate income tax, with top rates running from about 2% to over 11%. A few states have no corporate income tax but charge a gross receipts tax or franchise tax instead. Some also impose flat minimum taxes or annual filing fees whether or not you turn a profit. Any of these reduce the profit you actually keep.
Quarterly Estimated Payments
Owners who expect to owe $1,000 or more in tax generally must make quarterly estimated payments. Get these wrong and you can owe an underpayment penalty even if you pay the full balance by the filing deadline. Two safe harbors avoid it: pay at least 90% of the current year’s tax, or pay 100% of last year’s tax. If your prior-year adjusted gross income was over $150,000, the second threshold rises to 110%.11Internal Revenue Service. Underpayment of Estimated Tax by Individuals Penalty
That is the practical reason to track net profit month by month rather than once a year. If the first half was strong, waiting until April to discover you owe $40,000 means penalties and interest have already accrued. Missing the return entirely is worse: failure to file adds 5% per month on the unpaid balance, and failure to pay adds 0.5% per month.12Office of the Law Revision Counsel. 26 USC 6651 – Failure to File Tax Return or to Pay Tax
When the Number Is Negative
A net loss is not just a bad quarter on paper. Under current federal rules, a net operating loss (NOL) can be carried forward indefinitely to offset taxable income in future profitable years. Losses generally cannot be carried backward to claim refunds on prior-year taxes, with narrow exceptions for farming businesses.13Internal Revenue Service. Instructions for Form 172
There is a cap. NOLs arising after 2017 can offset only up to 80% of taxable income in any carryforward year. If the business earns $200,000 next year and you are carrying a $300,000 loss forward, you can use $160,000 of it (80% of $200,000), leaving $140,000 for later years. The remaining 20% of income is taxed normally.13Internal Revenue Service. Instructions for Form 172 Tracking carryforwards carefully is worth the effort. They are real future tax savings, and they are easy to forget to claim.