QuickBooks Online Projects is the most straightforward way to track job costs for skilled trades businesses like HVAC and plumbing. Each service call or installation gets its own Project. Every dollar you spend on that job gets tagged to that Project so you can see exactly what each job cost you and whether you made money on it.

To set it up, go to Settings, then Projects, and turn the feature on. Create a new Project for each job with the customer name and job description. From that point forward, every expense, bill, time entry, and invoice related to that job should be assigned to the Project when you enter it.

The categories you want to track for each job typically include materials and parts, labor hours, subcontractor costs, permits and inspection fees, and equipment rental. When you enter a bill from your supply house, assign it to the correct Project. When a technician logs hours, those hours should be tied to the Project. When you pay a subcontractor for work on a specific job, that bill goes to the Project too.

If your QBO plan doesn’t support Projects, Classes work as an alternative. Create a Class for each job and assign transactions the same way. The reporting is slightly different but the concept is identical.

The real value shows up when you compare your total job costs against what you invoiced. QBO’s Project profitability report pulls this together automatically. You’ll see revenue on top, all costs broken out below, and the profit or loss at the bottom. If you quoted a water heater install at $1,800 but your materials, labor, and drive time added up to $1,650, you only made $150. That’s the kind of visibility that changes how you price jobs.

Review unbilled costs weekly. This is where money falls through the cracks. A technician uses $200 in parts on a repair call and forgets to tell the office. The parts hit your supply house account but never make it onto the customer’s invoice. QBO can show you costs assigned to a Project that haven’t been invoiced yet. Make checking this part of your weekly routine.

Labor tracking is where most HVAC and plumbing businesses struggle. Technicians are busy running calls and don’t want to log time in an app. But if you don’t capture labor hours per job, your profitability numbers are wrong. Even a simple daily timesheet where techs write down which jobs they worked and for how long is better than nothing. Enter those hours into QBO weekly.

Get your team in the habit of noting the job number on every receipt and every purchase order. When someone buys fittings at the supply house, the job number should be on the ticket. This makes it much easier to assign costs correctly when the bill comes in rather than guessing which job consumed which materials.

Job costing only works if it happens consistently. One month of perfect tracking followed by two months of dumping everything into generic expense categories gives you unreliable data. If keeping up with this feels like too much on top of running service calls, our bilingual bookkeeping services can handle the categorization, reconciliation, and reporting so you get clean job profitability numbers without doing the data entry yourself.