5 Operating Numbers Every Trades Business Owner Should Know · Plumb Line

5 Operating Numbers Every Trades Business Owner Should Know.

You probably know some of these already, and that's the point. Knowing them on instinct is one thing. Knowing what they're telling you is another.

THE OPERATING DASHBOARD COST PER TRUCK THE DAILY FLOOR BILLABLE HOURS OF THE PAID DAY GROSS MARGIN WHAT'S LEFT DAYS TO GET PAID WORK TO MONEY $ CASH FLOW OPERATING

Five numbers. Each one tells you something the others can't.

You probably know some of these already. That's not a bad thing. But it's important to understand all 5 and how they relate to your business.

If you've been running a trades business for any real length of time, a few of these numbers are going to feel familiar. You may not call them by their textbook names, but you know them. You feel them in your gut every time you look at a bid, a paycheck run, or your bank balance on a Friday afternoon.

Still, worth walking through. The difference between an owner who's running the business and one who's being run by it usually isn't whether they've heard of these numbers. It's whether they can pick them up cold, off a P&L, and say out loud what's happening and what to do about it.

So that's what this is. Five numbers. What each one actually measures, why it matters, and what a healthy one looks like for a trades shop. Plain language, no MBA-speak.

A number you can't explain
is a number you can't fix.

01
The First Number

Cost Per Truck Per Day

The Real Floor On Your Pricing

Every truck you put on the road costs you money before it earns a dollar. The tech's wages and benefits. The fuel. The insurance. The phone. The software. The truck payment. A slice of the office rent, the dispatcher's salary, the bookkeeper. Add it all up, divide by the number of working days in the year, and you get your cost per truck per day.

The Formula
Annual Cost To Run One Truck ÷ Working Days Per Year

This is the floor. If a truck costs you $850 a day to put on the road and you only bill $700 that day, you lost money on that truck. Doesn't matter what the customer thinks of the work. Doesn't matter how busy you looked. The truck went out and came back lighter than it left.

Most owners have a rough sense of this. They'll tell you "we need to do about a thousand a day per truck" and they're usually in the neighborhood. The neighborhood isn't good enough at $2M and up. The number you want is precise, because once you know it, two things change. You bid differently. And you stop accepting work that can't clear the floor.

What To Watch
The number itself depends on your market and your mix; what matters is whether your average daily revenue per truck comfortably clears your cost. A 2x ratio (revenue is twice the cost) is a reasonable target for most service shops. Less than 1.5x, and you're working on borrowed time.

It also makes the question of "should I add another truck?" a math question instead of a feeling. If your existing trucks are clearing the bar by a comfortable margin, the next one probably will too. If they're scraping by, adding another truck just gives you another way to lose money.

02
The Second Number

Billable Hour Ratio

How Much Of The Day You Sell

You pay your techs for the whole day. Eight hours, ten hours, whatever it is. But you only bill the customer for the hours the tech is actually turning a wrench on the job. The drive between jobs, the trip to the supply house, the time spent looking for parts in the truck, the lunch break, the morning meeting. You pay for all of that, and none of it shows up on an invoice.

So here's the question: out of every hour you pay for, how many do you actually sell?

The Formula
Billable Hours ÷ Paid Hours

That's it. If a tech works a 40-hour week and you bill 24 of those hours to customers, your billable ratio is 60%. The other 40%, which is 16 hours every week per tech, is overhead disguised as payroll.

This one is sneaky because it doesn't show up cleanly on any single report. It hides inside your labor cost. You can have a great bid, a great crew, and a great customer, and still bleed margin because the drive time was an hour each way and nobody was counting.

Healthy Range
Good service operations push 65–75% billable. Project-heavy shops can run a little lower because mobilization eats more of the day. Anything under 55% and your scheduling, your routing, or your truck stock is costing you money you can't see on the P&L.

Move this number up two points and watch what happens to your bottom line. You didn't raise prices. You didn't add a tech. You just sold more of the day you were already paying for.

Revenue is the score. Cash is the oxygen.

03
The Third Number

Gross Profit Margin

What's Left After The Job

You probably think you know this one. And you probably do know the formula. But it's exactly what you're plugging IN to that formula where things often go wrong. Here's an example: Are you using your techs' hourly wage as their cost? If you are, your margin is smaller than you think it is.

Here's why. A tech doesn't cost the company what's on their pay stub. They cost the pay stub, plus your half of the payroll taxes, plus workers' comp (which in trades is one of the most expensive lines of insurance there is), plus health insurance, plus retirement contributions, plus PTO and holidays and sick days, plus the truck stock they burn through that never gets billed as materials. Add it all up, and a tech paid $30 an hour is actually costing the company closer to $42.

That gap between wage and true cost, usually 25 to 40 percent, is where a lot of shops quietly bleed margin. Bid a job assuming labor is $30 an hour and it'll look like a healthy 40% margin going in. Do the same job with labor actually costing $42, and the real margin lands closer to 22%. The P&L catches it eventually, because the P&L uses real payroll, not the number in your head. But by then you've spent the whole year running on figures rosier than reality.

And while we're on inputs going wrong: markup and margin aren't the same number. A 40% markup is a 29% margin. If you're pricing at "cost plus 40" and calling that a 40% margin, you're about 11 points off the number you think you're running.

Here's the simplest way to think about it. You finish a job. The customer pays you. Then you pay everything it took to do that job: the materials, the labor of the guys on the truck, the subs, the fuel, the disposal fees. Whatever's left over is your gross profit. Divide that by what the customer paid you, and you've got your gross margin.

The Formula
(Revenue Job Costs) ÷ Revenue

That number tells you whether the work itself is making money. Not the company. The work. Before you've paid yourself, before the office rent, before insurance, before the truck payments. Just: did the job, on its own, leave anything on the table?

This is the one most owners feel in their bones already. You bid a job at 40%, you finish a job at 28%, and you know in your stomach that something went sideways. Maybe the crew burned an extra day. Maybe materials came in hot. Maybe you priced it wrong from the start. The number tells you it happened. Looking job-by-job tells you why.

Healthy Range
For most trades shops, a gross margin of 35–45% is the zone you want to live in. Service-heavy work can run higher. New construction can run lower. Below 30% and you're working too hard for what's coming back.

There's another trap worth flagging: averaging. A 38% gross margin across the whole year sounds fine. But if it's 50% on service calls and 22% on installs, you don't have a 38% business; you have two different businesses, one of which is dragging the other one down. The number is only useful when you slice it.

04
The Fourth Number

Days To Get Paid

Also Known As DSO

This is the average number of days between sending an invoice and the money actually hitting your account. Accountants call it Days Sales Outstanding, which is a fancy name for a simple thing: how long is your money sitting in somebody else's bank account before it makes it to yours?

The Formula
(Accounts Receivable ÷ Revenue) × Days In Period

If you do $2M in revenue a year and you have $230,000 sitting in receivables on average, you've got a DSO of about 42 days. Which means the work you did six weeks ago is still funding somebody else's checking account, not yours.

Here's why this matters more than people realize. You can be profitable on paper and broke at the same time. The job priced out fine, you finished it, the customer is happy, but until they pay you've covered all of those costs out of your own pocket. Materials, payroll, fuel, all of it. The longer they take, the more of your money is floating out there propping up jobs you already finished. Every new job you start has to fight for cash that's locked up in old ones.

Healthy Range
Residential service work should be under 15 days; you should be collecting at completion. Commercial and project work runs longer, but if you're over 45 days, your billing process or your collections process is broken, and the business is financing it for free.

The fix is rarely glamorous. Invoice the day the job is done, not at the end of the week. Take cards on the truck. Tighten the payment terms in writing. Call about overdue invoices on day 31, not day 60. None of it is exciting. All of it converts to cash.

05
The Fifth Number

Operating Cash Flow

The One That Decides Everything

If the first four numbers are diagnostic, this one is the report card.

Operating cash flow is the cash the business actually generated in a period. Not the profit on paper, the cash. Money in the door from operations, minus money out the door for operations. Not money from loans. Not money from selling a truck. Just: did running the business this month put more cash in the account or take some out?

The Plain-English Version
Cash In From Operations Cash Out For Operations

Profit and cash are not the same thing, and that's the part that catches owners off guard. You can have a great profit number on the P&L and a shrinking bank balance, because the profit is tied up in receivables, in materials sitting in the warehouse, in deposits on jobs that haven't shipped. Profit is an accountant's calculation. Cash is what pays the crew on Friday.

The honest test of a healthy business is this: in a normal year, with no funny business, is the operating cash flow positive and growing? If it is, you can hire, you can invest, you can absorb a bad month. If it isn't, you're running on borrowed time even if the P&L looks fine.

What To Watch
Compare operating cash flow to net income over the same period. They should be in the same neighborhood. If profit is high but cash is flat, the money is stuck somewhere, usually in receivables, inventory, or work that's been done but not billed. Find it, free it.

This is also the number a banker, a buyer, or a partner will look at first. Profit gets you the meeting. Cash flow gets you the deal.

Five numbers. You already feel four of them. Now you can read them.

Why these five

There are a hundred numbers somebody could put in front of you. Most of them are noise. These five aren't, because between them they answer the questions that actually decide whether a trades business grows or stalls.

Cost per truck per day asks: what's the floor I can't bid under? Billable hour ratio asks: am I selling enough of the day I'm paying for? Gross margin asks: is the work itself making money? DSO asks: how fast does the work turn into money I can use? And operating cash flow asks the only question that ultimately matters: is this business, on its own, generating cash?

You don't need to look at all five every day. You do need to know them. Pull them once a month. Watch the trend. When one of them moves, ask why. That's the work.

None of this is glamorous, and none of it is what you signed up for when you started swinging a wrench. But the owners who break through the wall, the ones who get from $1M to $5M without losing their minds, they're the ones who got friendly with these numbers. Not because they love spreadsheets. Because they got tired of being surprised.

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