Understanding Profit and Loss Statements

Most owners receive a profit and loss statement every month from Xero or MYOB, glance at the bottom line, and move on. Some do not open it at all until tax time. That is a pity, because the P&L is the closest thing a business has to a monthly health check — and the useful information is rarely on the bottom line.

Reading a P&L is not an accounting skill. It is knowing what each section means, which numbers deserve attention, and what questions to ask when they move.

The shape of a P&L

• Revenue (income) — what you earned from customers over the period, normally shown excluding GST, because the GST was never yours.
• Cost of goods sold (COGS) — the direct costs of delivering that revenue: materials, stock sold, subcontractors, direct labour. These costs rise and fall with sales.
• Gross profit — revenue minus COGS. This is what is left to run the business after each sale pays for itself.
• Operating expenses (overheads) — rent, insurance, software, admin wages, marketing. These stay roughly the same whether you sell a lot or a little.
• Net profit — what remains after everything. The famous bottom line, and the least diagnostic number on the page.

Gross profit is the number to watch

Pricing problems, supplier price rises, quoting errors and job blowouts all land in gross profit first, months before they reach the bottom line. Watch gross profit as a percentage of revenue and follow the trend: if the margin is drifting down while sales hold steady, something in pricing or direct costs is moving against you, and cutting overheads will only hide it for a while. For this number to mean anything, direct costs must actually sit in COGS — a file where materials and subcontractors are scattered through the overheads produces a gross margin nobody can use.

Accrual and cash are different views

Most P&L reports are prepared on an accrual basis: income counts when invoiced, expenses count when billed, regardless of when money moves. That is the right way to measure performance, but it explains the eternal question — why does the profit not match the bank account? Unpaid invoices, loan repayments, asset purchases and your own drawings all sit outside the P&L. A cash-basis view is worth a look alongside it, but a business run on the cash view alone can look wonderful while its unpaid invoices quietly pile up.

What to look at each month

Compare the month against the same month last year and against your budget if you have one, since many businesses are seasonal and last month is a poor benchmark. Follow the gross margin trend, watch wages as a share of revenue, and scan for lines that jumped — a doubled software line or a missing rent entry usually means a bookkeeping error, and errors found monthly are easy to fix. Ten minutes with a consistent routine beats an hour once a year.

What we commonly see go wrong

• Only the bottom line gets read, so a declining gross margin hides behind one-off cost cuts until it cannot.
• Direct costs coded to overheads, making gross profit meaningless.
• Owner wages sometimes in the P&L and sometimes taken as drawings, so no two periods compare cleanly.
• Comparing against nothing — no budget, no prior year — so every number floats without context.

A worked example

As an illustration: a café's net profit looks steady all year. Underneath, supplier prices have been rising for months while menu prices stayed fixed, and the gross margin has been sliding the whole time — masked on the bottom line because the owner quietly cut their own hours and wages to compensate. Nobody looks at the margin line until the accountant prepares the year-end accounts, by which point a full year of underpriced coffee has been sold. A monthly glance at gross margin would have started the price conversation months earlier, while it was still a small adjustment.

When to get help

If your P&L does not resemble how you think the business is going, if gross profit means nothing because of how costs are coded, or if you want the report set up so the monthly read takes minutes, a one-off session with your accountant to restructure the chart of accounts usually pays for itself. We see this often — the problem is rarely the owner's numeracy, and usually the report's layout.

Why does my profit not match my bank balance?

Because the P&L measures performance, not cash. It counts invoices when issued and bills when received, and it excludes loan repayments, asset purchases, drawings and GST movements — all of which change the bank balance without touching profit.

Should I read my P&L on a cash or accrual basis?

Accrual is the better measure of how the business is actually performing, because it matches income to the period it was earned. The cash view is useful alongside it for understanding the bank account, but relying on cash alone can hide a growing pile of unpaid invoices.

How often should I review my profit and loss statement?

Monthly, with a consistent short routine: compare to the same month last year, check the gross margin trend, and scan for lines that moved unexpectedly. Waiting until year end means finding problems after a full year of them.