It's Friday at 7:15 PM and you're on the phone with your electrical sub. He says the invoice is right. You have your foreman's site notes in front of you — handwritten, coffee-stained — and they tell a different story. 47 hours on his bill. 41 in the notes. Neither of you is making this up. You just never agreed on the rules at the start of the job.

You end the call without resolving it, because the concrete pour starts at six tomorrow and you've got other things to think about.

That $192 discrepancy — before markup — will either get paid or turn into a conversation you don't want to have next week.

Two businesses, one site

An employee is your person. You know their occupation, their premiums, where they clocked in. Their timesheet, even an imperfect one, gives you something to work with.

A subcontractor is a separate operation. They have their own rules about what counts as a billable hour, their own understanding of travel time between work zones, their own definition of a full day. Their invoice reflects their reality. Not necessarily yours.

The friction starts when both logics run in parallel — same site, same deadline, same budget — and nobody's bothered to reconcile the ground rules first. At month-end, you're the one sorting it out.

Where it breaks down

The gaps almost always hide in the same places.

Arrival and departure times. Your foreman logs when people are on site. The sub bills from when his truck left the yard. Both are reasonable. But the gap between them adds up across a season.

Travel time between work zones. On a multi-trade site, your electrician moves equipment from one building to another. In his mind, that's billable time. In yours, maybe not. Nobody had the conversation.

Weather cuts. Rain hits at 2 PM, site shuts down. Your employees are paid to 2 PM. Your sub invoices the full day because that's how the contract was worded — and you could have written it differently if you'd thought to.

Unauthorized extras. The sub fixed a small problem outside his scope because it was right there and seemed quick. He added two hours to his bill. You find out on a Friday night reading through invoices.

None of this is fraud. These are grey zones nobody clarified when they came up. The cost shows up later, on your side of the ledger.

What you can do without overhauling everything

A few habits cut the majority of disputes off before they reach the invoice.

Write the rules into the purchase order, not after the fact. What's billable and what isn't, how travel time between zones gets counted, what happens when weather cuts the day short. Two paragraphs upfront are worth more than two hours of disagreement later. Start with the situations that have already burned you — you know exactly what to cover.

Keep a presence log for each site. Not to monitor anyone — to have a neutral reference point. If your foreman notes who's on site each morning and what time, you have something to compare when the invoice arrives. A simple note in his phone is enough.

Validate in real time, not in batches. When a sub wraps up a significant week, a quick check-in — "47 hours this week sound right to you?" — is worth more than a dispute call three weeks later when everyone's memory has drifted. People forget quickly. Notes don't.

Keep subcontractor costs separate from employee costs. They're two different lines with two different logics. Mixing them into the same spreadsheet makes your margins unreadable and complicates your end-of-project analysis.

How tracking your own crew helps you read the rest

Subcontractor management is a separate problem from managing your employees' payroll. But the two inform each other.

When you know exactly how many hours your own crew worked on a given site this week — by site, in real time — you spot the gaps faster when a sub's invoice doesn't line up with the surrounding picture. Your team clocked 310 hours this week on the Elm Street project and your painter is billing 90? You have a question to ask before you sign off.

This is something the contractors we work with notice after a few months: having a clear view of employee hours by site makes the rest more legible too. Labour costs become real numbers, not rough estimates — and that changes how you read an outside invoice.

If you want to see how this works in practice for a crew like yours, take 20 minutes with us.

Key takeaways

Subcontractors and employees operate under different logics — letting them coexist without a shared framework creates friction that lands on you
Most billing gaps come from grey zones nobody defined upfront: travel time, weather cuts, extras
A clear purchase order and a simple presence log eliminate most disputes before they escalate
Validating in real time costs less than reconciling at month-end
When you know your employee costs by site in real time, subcontractor invoices are easier to read — and easier to push back on when something doesn't add up