Gross margin, in plain language, for an owner-operator

Ask an owner-operator how the year went and you'll usually get a revenue figure. Ask what the gross margin was and you'll get a pause, then a guess, then a promise to check with the accountant.

That's not a failing of the owner. Revenue is visible every day and margin isn't visible at all unless somebody deliberately calculates it. But margin is the number that tells you whether the work is worth doing, and it's 1 of the core jobs in the money block set out in the guide to working on the business rather than in it.

Here's the whole calculation, what goes in it, and what it tells you once you have it.

What gross margin actually is

Gross profit is what's left of your revenue after you subtract the cost of delivering the work. Gross margin is that same figure expressed as a percentage of revenue.

Revenue minus cost of delivery equals gross profit. Gross profit divided by revenue, times 100, equals gross margin.

The word doing the work is "delivery". Gross margin deliberately ignores rent, insurance, your accounting fees, the ute payment and every other cost that exists whether or not a job runs this week. Those are overheads, and they come out further down the page.

That's why margin is such a useful early warning. It isolates the economics of the work itself. If margin is thin, no amount of overhead trimming saves you, because the problem is in the job rather than in the office.

What belongs in cost of delivery, and what doesn't

This is where most home-made calculations go wrong, and the error nearly always runs the same way: the owner's own labour is left out, so the margin looks healthy.

Generally in. Materials and consumables for the job. Wages and on-costs for the people doing the work, including your own time at a real rate. Subcontractors. Equipment hire for a specific job. Freight and delivery. Merchant fees where they scale with sales. Direct site costs.

Generally out. Rent. Insurance. Vehicle finance and registration. Software subscriptions. Marketing. Administrative wages. Accounting fees. Interest. Anything that would still arrive as a cost in a month with no work in it.

There are grey items, and vehicles are the usual argument. A ute that exists whether or not there's a job is an overhead. Fuel burnt driving to a specific site is closer to a delivery cost. Pick a treatment, write it down, and use the same one every time. Consistency matters more than perfection here, because the value of the number comes from comparing it to last quarter's number.

Talk to your accountant about how the categories are set up in your accounting file so the report you pull matches the way you think about the work. That mapping is a 20-minute conversation and it makes the number trustworthy for years.

Working it out: an illustration with round numbers

This is an illustration, not a real business. Take a service business with $500,000 of revenue in a year. Wages and on-costs for delivery come to $250,000, materials to $60,000, and subcontractors to $15,000. Cost of delivery totals $325,000. All figures ex GST.

Gross profit is $500,000 minus $325,000, which is $175,000. Gross margin is $175,000 divided by $500,000, which is 35%.

Now the sentence that makes it useful: overheads have to come out of that $175,000, and so does the owner's return. If the same illustrative business runs $150,000 of overheads, there's $25,000 left. That business is busy, banked half a million, and has almost nothing to show for the year.

Nothing about that illustration predicts what any real business will do. It shows the shape of the arithmetic, which is the part owners rarely see laid out.

Markup is not margin

The single most expensive confusion in small business pricing. Markup is calculated on cost. Margin is calculated on price.

Add 50% markup to an item costing $100 and you charge $150 ex GST. The margin on that sale isn't 50%, it's $50 divided by $150, which is 33%. An owner who thinks a 50% markup is a 50% margin is short by a third every time, and it compounds across every job in the year.

Do it by job type, not just for the whole business

A whole-of-business margin is a blended average, and averages hide the thing you need to see.

Split revenue into the 4 or 5 lines you actually sell: service calls against installations, maintenance against projects, retail against wholesale, whatever the real categories are. Then run the same calculation on each.

What comes out is almost always uneven, and usually not in the direction the owner expected. The line that feels busiest is frequently the thinnest. The small awkward jobs nobody enjoys are frequently the strongest.

That single view changes decisions. It tells you which work to chase, which to reprice, which to quote more carefully, and occasionally which to stop offering. It also feeds straight back into the price, because how to price your services builds the number up from a cost per productive hour that this exercise gives you.

You need job-level cost data to do it, which means recording actual hours against jobs rather than quoted hours. If that data doesn't exist yet, start capturing it now on new jobs. A quarter of real data beats a year of estimates.

What a falling margin is telling you

Margin moves for a small number of reasons, and knowing which one is in play matters more than the movement itself.

• Input costs rose and the price didn't. The most common cause, and the slowest to notice, because it arrives 2% at a time. Fixing it means a price review, which is what raising your prices without losing your customers works through.
• Jobs are taking longer than quoted. Scope creep, rework, or a quote built on optimistic hours. The tell is a normal-looking margin on small jobs and a poor one on large ones.
• Discounting has become a habit. Not a policy, just a reflex at the end of a quote conversation. It rarely shows up anywhere except margin.
• The mix has shifted. Volume moved towards the lower-margin line without anybody deciding it should. Nothing is broken, but the business is quietly becoming a different business.

Margin percentage and margin dollars can also move in opposite directions, and both readings matter. A bigger job at a lower percentage can still deliver more dollars, which is a legitimate trade when capacity is spare and a bad one when it isn't.

Your registered tax agent handles tax. A coach works on what the business does to make the money in the first place: what you charge, what delivery costs, and which work is worth taking. How the numbers are reported and classified belongs with your accountant.

What to do with the number once you have it

Calculate it monthly, by job type, and put it on the short list of figures you can quote without opening anything. The numbers every owner should know covers what else belongs on that list.

Then hold 1 rule in your head: margin is a profit measure, not a cash measure. A job can carry a strong margin and still leave you short in the account, because margin says nothing about when the money arrives. That gap is a separate problem, and why profitable businesses still run out of cash explains how it opens up.