Getting this wrong doesn’t just mess up your books. It distorts your job profitability numbers, which means you’re making bidding and pricing decisions based on bad data. A job that looks profitable might actually be breaking even once insurance costs are properly allocated.

General liability premiums are typically calculated based on payroll or gross receipts, which makes them allocable to individual jobs. If your GL premium is driven by payroll dollars, distribute that cost across jobs proportionally based on the labor hours or payroll charged to each project. This gives you a much more accurate picture of what each job actually costs.

Workers compensation works the same way. Your comp premiums are directly tied to payroll by classification code. When you run payroll for a framing crew on a specific project, the associated workers comp cost belongs to that project. Allocate it based on the job payroll that generated it. This is one of the biggest insurance line items for most contractors, so getting this allocation right has a real impact on your construction job costing.

Builder’s risk insurance on a specific project is a direct job cost, period. You bought that policy because of that project, and it covers that project alone. There’s no allocation math to figure out. It goes straight to the job.

Performance and payment bonds tied to a specific contract are also direct job costs. The premium you paid to bond that particular project exists because of that project. Charge it there. However, the general cost of maintaining your bonding capacity and your bonding relationship is overhead. That’s a cost of being in business, not a cost of any one job.

General commercial insurance belongs in overhead. Your business owner’s policy, commercial auto for your fleet, umbrella coverage, professional liability, and office-related policies all protect the business broadly. They don’t fluctuate based on any single project, so trying to allocate them per job creates false precision without adding useful information.

The practical question is how much overhead markup to apply when bidding. If your overhead insurance costs run $4,000 a month and you’re running four jobs, a simple allocation might put $1,000 on each. But your actual overhead recovery should be built into your markup percentage across all jobs, not arbitrarily split.

For the job-level allocations, set up your accounting software to track GL and workers comp as a percentage applied to each job’s labor costs. Many Phoenix bookkeepers who work with contractors build this into the chart of accounts so it flows automatically rather than requiring manual calculation every month.

One thing to watch for is your year-end audit adjustment. Workers comp and GL premiums are often based on estimates, with a final audit that adjusts for actual payroll. When that audit generates an additional premium or a refund, allocate that adjustment back across jobs proportionally. Don’t just dump it into overhead or you’ll undo all the careful tracking you did during the year.

The goal is that when you look at a completed job’s profitability report, the insurance costs that were driven by that job’s activity are reflected in the numbers. Everything else flows through overhead and gets recovered through your markup. That’s how you know which jobs actually made money and which ones just looked like they did.