Profit and loss statements

Why it matters

The P&L is where most profit problems become visible first. A gross margin that slips two points a quarter, a wages bill growing faster than revenue, a product line whose cost of sales has crept past its price: none of these shows up in the bank balance until it is too late to fix cheaply. Owners who read their P&L every month and compare it to last month and last year catch these drifts early. The P&L is also the document lenders, buyers and the ATO rely on to judge the business, so understanding it is understanding how others see you.

Revenue and cost of sales: the trading engine

Revenue is the value of what you sold in the period, excluding GST (GST is never income; it passes through to the ATO). Under accrual accounting it is recorded when the sale is made, not when cash arrives. Split revenue into a few meaningful lines, such as product versus service or one location versus another, so the P&L can show which parts of the business are growing.

Cost of sales (or cost of goods sold) is every cost that exists only because you made a sale: materials, stock sold, subcontractors, direct labour on jobs, merchant fees and delivery. If you sold nothing this month, these costs would be close to zero. The test for whether a cost belongs here is simple: does it go up when sales go up? Classifying it correctly is what makes gross margin meaningful.

Gross margin: the most important number on the page

Gross profit is revenue minus cost of sales. Gross margin is gross profit as a percentage of revenue. It tells you how much of each dollar of sales is left to pay for everything else, and it is the purest measure of whether your pricing and your direct costs are in balance. A café running at 65% gross margin keeps 65 cents of every dollar to pay rent, wages and itself; a wholesaler at 25% keeps a quarter.

Gross margin is also the number that moves first when something goes wrong. A supplier price rise, discounting to win work, waste on jobs or a shift in sales mix toward lower-margin products all show up as a falling gross margin months before net profit collapses. Track it monthly by product line where you can.

Operating expenses and net profit

Operating expenses are the cost of keeping the doors open whether or not you sell anything: rent, salaries and on-costs for non-production staff, marketing, software, insurance, vehicles, utilities, professional fees and depreciation. Group them so the P&L shows a dozen lines, not eighty. Subtracting them from gross profit gives operating profit; after interest and tax you reach net profit, the bottom line.

Net margin is net profit as a percentage of revenue. It varies enormously by industry, so compare it to your own history and to businesses like yours rather than to a universal benchmark. The useful habit is to read the P&L as percentages of revenue as well as dollars: if wages were 38% of revenue last year and are 44% this quarter, the dollars might look fine while the business is quietly losing its shape.

What the P&L cannot tell you

The P&L does not show cash. Loan principal repayments, equipment purchases, stock bought but not yet sold, GST and owner drawings all move cash without appearing as expenses. A profitable P&L and an empty bank account are entirely consistent. Read the P&L alongside the balance sheet and a cash forecast, and treat it as one of three views, not the whole picture.

How to read your P&L every month

1. Close the month first Reconcile all accounts and code every transaction. An unreconciled P&L is a guess.
2. Check cost of sales classification Every cost that moves with sales belongs above gross profit. Fix misclassifications before reading further.
3. Read it as percentages Show every line as a share of revenue. Compare to last month, the same month last year and your budget.
4. Investigate gross margin first Any movement of more than a point or two needs a reason: price, cost, waste or mix.
5. Scan operating expenses for creep Software subscriptions, vehicle costs and wages are the usual culprits. Question anything that grew faster than revenue.
6. Write three observations and one action The P&L is only useful if it changes something you do next month.

Real-world example

A Sunshine Coast café finds its missing margin

Marlin Espresso turns over $480,000 a year excluding GST. The owner, Sofia, has always judged the business by whether there was money in the account at month end. Her accountant builds a proper P&L: cost of sales (coffee, milk, food, packaging) is $168,000, a gross margin of 65%. Wages are $192,000 (40%), rent $48,000 (10%), other overheads $48,000 (10%), leaving a net profit of $24,000, or 5%, before she pays herself anything beyond casual drawings.

Reading the P&L by month, Sofia notices gross margin has slid from 68% to 63% over a year while sales were flat. Splitting cost of sales shows milk and food costs up sharply but prices unchanged since opening. She lifts prices by an average of 6%, trims a low-margin lunch menu, and renegotiates her milk supply. Three months later gross margin is back to 67%, which on her revenue is worth around $19,000 a year, nearly doubling net profit without a single extra customer.

Common mistakes

• Reading only the bottom line Net profit tells you the result, not the cause. Gross margin and expense ratios tell you what to fix.
• Burying direct costs in overheads If subcontractors or materials sit in operating expenses, gross margin looks wonderful and means nothing.
• Comparing dollars instead of percentages Expenses in dollars rise with growth. Expenses as a share of revenue show whether the business is getting better or worse.
• Leaving owner wages off Unpaid founder labour hides a loss. Include a market salary before deciding the business is profitable.
• Confusing profit with cash Loan repayments, equipment and GST never appear on the P&L. Read it with the balance sheet and a cash forecast.

KPIs to track

• Gross margin % Gross profit divided by revenue. The first number to watch each month; investigate movements of more than two points.
• Net margin % Net profit divided by revenue, after a market-rate owner salary. Compare to your own history and your industry.
• Wages as % of revenue The largest overhead in most service businesses. A rising ratio with flat sales means productivity or pricing has slipped.
• Revenue per employee Total revenue divided by full-time-equivalent staff. A simple productivity measure to track year on year.
• Break-even revenue Fixed costs divided by gross margin %. The monthly sales you need before any profit appears.

Frequently asked questions

What is a good net profit margin?

It depends heavily on industry: a software business and a supermarket operate at completely different margins. Compare against your own trend and against similar businesses, and remember to include a proper owner salary first.

Why does my P&L show profit when my bank account is empty?

Because cash items such as loan principal, equipment, stock and GST do not appear on the P&L, and because customers may not have paid for sales already recorded. The balance sheet and a cash flow forecast fill in the gap.

How often should I look at my P&L?

Monthly, within ten days of month end, with comparisons to the prior month, the same month last year and budget. Quarterly is too slow to catch margin drift.

Is depreciation a real expense?

Yes. It spreads the cost of equipment and vehicles over the years they are used, so the P&L reflects the true cost of operating. It does not involve cash in the period, which is one reason profit and cash differ.

Key takeaways

• Read the P&L top to bottom: revenue, cost of sales, gross profit, overheads, net profit.
• Gross margin is the first number to watch; it moves before anything else does.
• Express every line as a percentage of revenue and compare across periods.
• Include a market-rate owner salary before judging profitability.
• The P&L does not show cash; read it alongside the balance sheet and a forecast.