A profit and loss statement, often called a P&L or an income statement, is a financial document that summarises a business's revenue, costs, and net profit or loss over a defined period. It could cover a month, a quarter, or a full financial year. Unlike a snapshot document, it tells a story over time: money came in, money went out, and here's what remained.
Understanding a P&L is not just an accountant's job. If you run a business, manage a team with a budget, or invest in companies, reading a profit and loss statement is a core skill. It tells you whether the business is genuinely profitable, where costs are growing faster than revenue, and whether growth is sustainable or just activity.
What a profit and loss statement contains
Every P&L follows the same basic structure, from the top line down to the bottom line.
Revenue sits at the top. This is the total income generated from selling goods or services before any costs are subtracted. It's sometimes called "turnover" in Australian accounting practice. Revenue alone doesn't tell you whether a business is healthy. A company can have strong revenue and still lose money.
Cost of goods sold (COGS) comes next. This is the direct cost of producing whatever the business sells: raw materials, labour on the production floor, freight for goods delivered. COGS moves in line with sales volume. When COGS is subtracted from revenue, the result is gross profit.
Operating expenses follow. These are the costs of running the business that aren't directly tied to each unit of production. Rent, salaries for administrative staff, marketing, insurance, software subscriptions. Subtracting operating expenses from gross profit gives you operating profit, also called EBIT (earnings before interest and tax).
Below that come interest expenses and tax. Once both are subtracted, the final figure is net profit (or net loss). This is the famous "bottom line." It's the clearest single number for whether the business made money in that period.
How it differs from a balance sheet and cash flow statement
Business owners sometimes confuse the P&L with the other two core financial documents. The distinction matters.
A balance sheet shows what a business owns and owes at a single point in time. It's a snapshot of assets, liabilities, and equity. The profit and loss statement, by contrast, covers a period of activity. The two documents connect: net profit from the P&L flows through to equity on the balance sheet at the end of each period.
Cash flow is a separate matter again. A business can show a profit on its P&L and still run out of cash. That happens when revenue is recorded before customers actually pay, or when large expenses fall due at once. Cash flow tracks the actual movement of money in and out of the business. The P&L records income and expenses when they're earned or incurred, regardless of when cash changes hands. This is the difference between accrual accounting and cash accounting, and it's why profitable businesses can still fail.
What a P&L actually reveals
A single P&L gives you a number. A series of them gives you a picture. Comparing P&Ls across multiple periods shows whether revenue is growing, whether margins are holding, and whether a cost category is quietly ballooning.
Gross profit margin is one of the most useful ratios to pull from a P&L. It's calculated as gross profit divided by revenue, expressed as a percentage. A business with $500,000 in revenue and $300,000 in COGS has a gross profit of $200,000 and a gross margin of 40%. If that margin was 48% two years ago, the business is losing ground on its core economics, even if total revenue has grown.
Net profit margin works the same way at the bottom line. A business reporting $50,000 net profit on $1 million revenue has a 5% net margin. Whether that's strong or weak depends heavily on the industry. Supermarkets operate on margins under 3%. Software companies can exceed 25%.
Operating expenses as a share of revenue is another ratio worth tracking. It reveals whether the business is scaling efficiently. If revenue doubles but operating expenses triple, the business has a cost structure problem, regardless of what the top line looks like.
Common mistakes when reading a P&L
Focusing only on revenue is the most common error. Strong top-line growth can mask deteriorating margins and rising costs. Revenue is where the conversation starts, not where it ends.
Ignoring depreciation is another trap. Depreciation is a non-cash expense that spreads the cost of an asset over its useful life. It appears on the P&L and reduces reported profit, even though no cash left the bank in that period. Some business owners try to dismiss it as "just accounting," but it reflects real economic wear on equipment, vehicles, and infrastructure.
Treating the P&L as a once-a-year document is a mistake that small business owners make repeatedly. Monthly or quarterly P&L reviews give you time to respond to problems before they compound. An annual review only tells you what went wrong. It doesn't give you room to fix it.
Who uses a profit and loss statement
Business owners use P&Ls to track performance and guide decisions on hiring, pricing, and investment. Banks and lenders review them before approving credit. Investors study them before committing capital. The Australian Taxation Office requires them as part of business tax reporting.
If you're considering buying a business, the P&L for the past 3 years is one of the first documents you'd request. It shows whether the business actually earns what the seller claims, and it often reveals costs that a casual inspection wouldn't surface.
For anyone building a new venture, projecting a P&L is part of the planning process. You're estimating future revenue, mapping expected costs, and identifying the point at which the business stops losing money. That intersection connects directly to understanding your break-even point, which is the moment revenue covers all costs and net profit reaches zero.
A P&L won't tell you everything about a business. But read carefully, compared across time, and set alongside the balance sheet and cash flow statement, it tells you more than almost any other single document.