What Is a WIP Schedule and Why Does Every Subcontractor Need One

If you've ever applied for bonding, submitted financials to a bank, or tried to get a line of credit as a construction subcontractor, someone has probably asked you for a WIP schedule.

Most subcontractors either don't have one or hand over something that doesn't say what it should say. That's a problem — not just for bonding and banking, but for running your business.

Here's what a WIP schedule actually is, why it matters, and what it tells you that your P&L never will.

What WIP stands for and what it tracks

WIP stands for work in progress. A WIP schedule is a report that shows the financial status of every active job at a point in time.

For each job it shows:

- The total contract value

- How much the job has cost to date

- What percentage of the work is complete

- How much revenue has been recognized based on that completion percentage

- How much has actually been billed

The comparison between what should have been billed and what was actually billed is where it gets interesting. That comparison tells you whether each job is overbilled or underbilled — and that matters a lot more than most subcontractors realize.

Overbilling and underbilling — what they actually mean

Overbilling means you've collected more from the GC than the percentage of work you've actually completed justifies. You billed for 40% of the contract but you've only done 30% of the work. You're ahead on billing relative to the work in place.

Overbilling isn't necessarily bad — front-loading your schedule of values to recover mobilization costs creates a temporary overbilled position that's entirely intentional and legitimate. But persistent overbilling across a job that isn't front-loaded can indicate a problem: you're collecting cash now that you haven't earned yet, and you'll have to catch up with actual costs later.

Underbilling means the opposite. You've completed more work than you've billed for. You've done 50% of the job but only billed 35% of the contract value. You're behind on collecting what you've earned.

Underbilling is the more dangerous condition for most subcontractors. It means cash is going out faster than it's coming in. Your bank account is being drained by costs you've incurred but haven't yet billed. And if you're underbilled across multiple active jobs simultaneously, the cash pressure compounds fast.

Why your P&L doesn't show you this

The profit and loss statement shows you revenue and expenses over a period of time. It tells you the company made money or lost money. What it doesn't tell you is whether that revenue number is real.

Here's the problem. In construction, revenue gets recognized based on percentage of completion — not based on when the check arrives. If you're 60% done on a $1M job, your P&L recognizes $600,000 in revenue even if you've only collected $400,000.

That $200,000 gap between recognized revenue and collected cash is real — it's money you've earned and are owed — but it's also money that's not in your bank account. If you're underbilled, your P&L looks better than your bank account. If you're overbilled, your P&L looks worse than your bank account (temporarily).

Without a WIP schedule, you can't see this. You're looking at revenue numbers on a P&L that may or may not reflect what's actually happening on active jobs. The WIP schedule makes it visible.

A real example of what WIP catches

A $7M civil subcontractor we work with was running six active jobs when we started building WIP schedules for them. The P&L looked reasonable — margins were within range of what was expected.

The WIP schedule told a different story on two of the six jobs.

Job 1 was 65% complete but only 48% billed. They had $180,000 in unbilled earned revenue sitting there because billing hadn't kept pace with the work. Nobody had caught it because nobody was looking at percent complete relative to billing position.

Job 2 was overbilled — 40% billed but only 28% complete. That's not necessarily a problem if it was intentional front-loading, but in this case it wasn't. The billing had been aggressive early and now costs were catching up. By the end of the job they'd be showing a lower billing position than actual costs, which would hurt their cash position at closeout.

We addressed both. The underbilled job got a catch-up billing on the next pay app. The overbilled job got a revised cost-to-complete estimate to understand whether it was going to close at the expected margin.

Without the WIP schedule, neither of these would have been visible until the jobs were done.

Why bonding companies and banks care so much about WIP

Lenders and bonding companies aren't looking at your WIP schedule to be bureaucratic. They're looking at it because it's the only way to assess whether your financial statements are accurate.

A balance sheet for a construction company can show a healthy receivables number — but without WIP, there's no way to know if those receivables are real. Are they backed by work actually performed and billed? Or are they overbilled positions that will reverse before the job closes?

A bonding company that's underwriting $5M in bonds on your behalf needs to know the difference. If your receivables are real and your WIP shows you're properly billed relative to completion, they'll extend capacity. If your WIP shows persistent underbilling or jobs in loss positions, they're looking at a different risk picture.

For a $7M civil subcontractor trying to bond jobs over $3M, clean WIP reporting isn't optional. It's the difference between getting the bond and not getting it.

How to build a basic WIP schedule

You need four things for each active job:

1. Revised contract value — the original contract plus approved change orders. Not what was originally bid. What the current contract says.

2. Costs incurred to date — everything spent on the job through the reporting date. This comes from your job costing system.

3. Estimated cost to complete — what you think it will cost to finish the job from today. This is a PM judgment call, updated monthly. It's the most important number in the WIP schedule and the one most often done wrong.

4. Billings to date — what you've actually invoiced the GC through the reporting date.

From those four numbers, you can calculate percent complete (costs to date divided by total estimated costs), revenue earned (percent complete times contract value), and the overbilled/underbilled position (billings to date minus revenue earned).

The estimated cost to complete is where most WIP schedules fall apart. If the PM is optimistic — assuming the job will close at budget when it's clearly running over — the WIP schedule is misleading. The cost-to-complete estimate has to be honest, updated monthly, and based on what's actually happening on the job.

How often to update the WIP schedule

Monthly. Every billing cycle.

The WIP schedule should be updated every time a pay app goes out so the billing position is current. The cost-to-complete estimate should be revisited by the PM monthly — not just at project closeout.

For subcontractors running multiple large jobs simultaneously, a monthly WIP review with the PM team is one of the highest-value meetings you can have. It surfaces underbilling to catch up, identifies jobs developing cost overruns before it's too late to act, and gives the owner a real picture of financial exposure across the entire portfolio.

The bottom line

A WIP schedule is not just a document you produce for your banker. It's a management tool that shows you whether your active jobs are performing the way you think they are.

If you're underbilled, you need to catch up before cash runs out. If you're overbilled, you need to understand whether costs are coming. If a job's cost-to-complete estimate says it's heading for a loss, you need to know now — not at closeout.

The subcontractors who manage WIP actively don't get surprised at job closeout. They see the problems developing in month two or three, when there's still time to do something about them.

That's the whole point.