WIP stands for Work in Progress. It’s a financial schedule that shows where you stand on all your incomplete projects at any given time. For contractors working on jobs that span multiple months, WIP reporting is how you know whether your books reflect reality or just a misleading snapshot.

The basic idea is comparing what you’ve billed against what you’ve actually earned on each project. If you’ve billed $100,000 on a job but only completed $80,000 worth of work based on costs incurred, you’re overbilled by $20,000. That money isn’t really yours yet. You still owe that work to the customer. Without WIP, your income statement shows revenue you haven’t actually earned.

The opposite happens too. If you’ve completed $120,000 worth of work but only billed $100,000, you’re underbilled by $20,000. Your books are understating your revenue because you have legitimate earnings that haven’t been invoiced yet.

WIP reporting tracks these overbillings and underbillings across all your active projects. When you add them up, you get adjustments that show what your financial statements should actually say. A contractor who looks profitable on paper might actually be overbilled on most of their jobs, meaning that “profit” is just money they haven’t earned yet.

You probably need WIP reporting if your projects regularly take more than 30 days to complete, you do progress billing based on milestones or percentage complete, or you want accurate financials that reflect real job profitability. Bonding companies require WIP schedules because they know a contractor’s standard financial statements don’t tell the full story. Banks often ask for them too when evaluating construction loans.

If you only do small jobs that start and finish within a week or two, you probably don’t need formal WIP reporting. The overbilling and underbilling swings are minor enough that they wash out. But once projects stretch into months, the distortion gets significant enough to matter.

Getting WIP right requires solid construction job costing first. You need accurate cost tracking by project so you can calculate percentage complete. If your job costs are a mess, your WIP numbers will be meaningless. The schedule is only as good as the data feeding into it.

WIP also affects your taxes. Depending on your accounting method, the IRS may require you to recognize revenue based on percentage of completion rather than when you bill. Your accountant needs WIP data to calculate this correctly. Ignoring it can mean either paying taxes on income you haven’t received or deferring taxes on income you’ve already earned.

Most contractors I work with as a construction bookkeeper in American Fork don’t realize how much their financials are off until they see their first real WIP schedule. It’s eye-opening to discover that the profitable quarter you thought you had was actually just overbilling that will reverse out when those jobs finish.

If you’re a general contractor, custom home builder, or anyone running projects that span multiple months with progress billing, WIP reporting isn’t optional. It’s the only way to know what’s actually happening financially in your business.