30-Second Overview

An income statement, also called a profit and loss statement or P&L, measures whether a business made money over a stretch of time by comparing the revenue it earned against the expenses it took on to earn it. The number at the bottom, net income or net loss, is the answer. Everything above that line exists to show how the business got there.

Related Terms and Concepts

Synonyms: Profit and Loss Statement, P&L, Statement of Operations

Related: Balance Sheet, Statement of Cash Flows, Statement of Owner's Equity, Gross Profit Margin, Cost of Goods Sold, Operating Expenses, Net Income, Revenue Recognition

Income Statement

An income statement reports how a business performed over a period: a month, a quarter, a year. It is the first of the four core financial statements a business prepares, and the number it produces (net income) feeds directly into the next one, the statement of owner's equity. The whole document exists to answer a single question. Did the business bring in more than it spent, and by how much.

The Four Things That Land On It

Four kinds of items make up an income statement: revenue, expenses, gains, and losses. Revenue is the value of goods or services the business actually sold or provided during the period, whatever a landscaper collects from clients or a coffee shop collects from drinks and pastries. Expenses are the costs of providing those goods and services: wages, rent, ingredients, insurance. When revenue is bigger than expenses, the business has net income. When expenses win, it has a net loss.

Gains and losses work the same way but come from something outside the business's main line of work, like selling a piece of unused land for more or less than it cost. Because they are one-off, a business that leans on them for its profit is telling you something different than one earning steady revenue. The full relationship is usually written as a plain subtraction:

Net Income = Revenue - Expenses

Add gains and losses when they exist:

Net Income = (Revenue + Gains) - (Expenses + Losses)

A Real One, Line by Line

Picture a small popcorn shop that just opened for the month of June. Revenue for the month comes to $85,000. Add up rent, wages, ingredients, and every other cost, and total expenses land at $79,200. Revenue exceeds expenses, so the shop has net income of $5,800 for June.

That plain example carries the formatting conventions every income statement follows. The heading always has three lines: the business name, the words "Income Statement," and the time period covered, since an income statement always covers a stretch of time rather than a single moment. The body typically runs three columns: the account name, a column for listing several accounts within one category (several expense lines, for instance), and a final column for subtotals. A single underline marks a subtotal on the way to the answer. A double underline marks the final number, net income, because nothing follows it.

Single-Step Versus Multi-Step

Businesses get to choose how much detail their income statement shows, and the choice usually comes down to two formats.

A simple, or single-step, income statement lumps all revenue into one line, all expenses into another, and subtracts to get net income. It has almost no individual accounts. It suits a small business or an outside reader like an investor who wants the headline number without wading through detail.

A multi-step income statement breaks the same numbers apart and shows the work. It separates cost of goods sold from every other expense and subtracts it from net sales first, producing gross margin. That distinction matters because cost of goods sold tracks the direct cost of making what got sold, while everything else is the daily cost of running the business regardless of sales volume. From gross margin, the statement subtracts operating expenses, split into selling expenses (advertising, sales staff) and general and administrative expenses (office supplies, depreciation on office equipment), to arrive at income from operations. Only after that does it add or subtract other revenue and expenses that have nothing to do with selling the core product, things like interest income or a gain on selling old equipment, to land on the same net income figure the simple version would have shown all along.

Both formats end at the identical number. They just disagree about how much of the path there to show.

Reading Quality Into the Number

Two businesses can report the same net income and deserve very different amounts of trust. One earned it through revenue, the ongoing value of what it actually sells. The other padded it with a gain from something like selling a building. Accountants call the first kind high quality, or permanent, earnings, and the second temporary earnings, because it will not repeat next period. A net loss deserves the same scrutiny in reverse. A loss caused by weak ongoing operations is a bigger warning sign than a loss caused by a one-off write-down, because operations are what a business actually depends on to survive.

Turning the Number Into a Ratio

Once operating expenses show up, the multi-step format supports a ratio that a single-step statement cannot: the gross profit margin ratio, which divides gross margin by net sales. A business with net sales of $293,500 and cost of goods sold of $180,000 has a gross margin ratio of about 0.39, meaning 39 cents of every sales dollar remains after covering the direct cost of the product. That remaining margin is what has to cover every operating expense and still leave something over for profit. A thin margin leaves almost no room for a bad month. A wide one gives a business room to reinvest, pay down debt, or return money to its owners.

TLDR

Net income is not a balance that carries forward on its own. It is the answer to one calculation for one specific period, and the next period starts from zero again. The format a business picks, single-step or multi-step, changes how much of the arithmetic gets shown but never changes the final number, so do not read more detail into a simple statement's absence of line items than is actually there. And when you are handed a net income figure, ask where it came from before you trust it. A number built on steady revenue and a number built on a one-time gain can look identical at the bottom of the page and mean completely different things about whether the business can do it again next month.