WIP reporting is an accounting method that shows you whether jobs in progress are actually profitable before they finish. Instead of waiting until a project closes to find out if you made or lost money, WIP calculations tell you where you stand while work is still underway.

Standard bookkeeping doesn’t handle long jobs well. Say you’ve billed a customer $50,000 on a project and recorded $30,000 in costs so far. Your books show a healthy profit. But if the remaining work will cost another $35,000, that job is actually losing money. Without WIP reporting, you won’t know until it’s too late to do anything about it.

The calculation compares three things. What you’ve spent so far, what you expect to spend total, and what you’ve billed. From these numbers you can determine how much revenue you’ve actually earned based on the percentage of work completed.

Here’s a practical example. You have a $100,000 contract with estimated total costs of $80,000. You’ve spent $40,000 so far, putting you at 50% complete. At 50% complete, you’ve earned $50,000 of that contract value. If you’ve billed $60,000, you’re overbilled by $10,000. That extra $10,000 is cash in your account but it’s not earned revenue. It belongs on the liability side of your balance sheet until you do the work to earn it.

Overbilling isn’t necessarily bad. Many contractors bill ahead intentionally to manage cash flow. But you need to know when you’re doing it because that money has strings attached. Spend it assuming it’s profit and you might run short before the job is done.

Underbilling is the opposite problem. You’ve completed more work than you’ve billed for. This strains cash flow and typically happens when contractors focus on production and fall behind on invoicing. Job costing tied to WIP reporting catches underbilling before it becomes a cash flow crisis.

Bonding companies and banks care about WIP because it reveals your real financial position. A contractor with $500,000 in the bank might look solid until a WIP schedule shows they’re overbilled on several projects. That cash isn’t really theirs to spend freely.

Setting up WIP reporting requires accurate cost tracking by project. Every expense needs to be assigned to the correct job, and your estimated costs to complete need to be updated as conditions change. If material prices jumped or you hit unexpected site conditions, those revised estimates affect your WIP numbers.

Most contractors working on projects over $25,000 or lasting more than a month benefit from WIP reporting. Monthly updates keep you informed without creating excessive paperwork. If your current books just show overall revenue and expenses without project-level detail, you’ll need that foundation in place first. Small business bookkeepers in Northern New Mexico who understand construction can help you set up the tracking systems that make WIP reporting possible.