How to Build and Read a Construction WIP Schedule

If there's one report that separates contractors who scale from contractors who stall, it's the work-in-progress schedule — the WIP. It's the report your surety asks for, your banker studies, and your CPA uses to recognize revenue correctly. Most contractors either don't have one or don't know how to read it. Here's how it works.

What a WIP Schedule Actually Is

A WIP schedule is a single table listing every open job and answering one question for each: based on how far along the job is, have you billed the customer too much, too little, or about right? It reconciles what you've spent, what you've earned, and what you've invoiced — and the gaps between those three numbers tell you the financial truth about your projects that your bank balance never will.

For a contractor using the percentage-of-completion method, the WIP schedule isn't optional bookkeeping — it's how your financial statements are built. Get it wrong and every number downstream is wrong too.

The Numbers That Drive It

Each job on a WIP schedule carries a handful of core figures: the total contract price (including approved change orders), the estimated total cost to complete, the actual cost incurred to date, and the amount billed to date. From those, two calculated numbers do the real work.

Percent complete is cost-to-date divided by estimated total cost. If you've spent $600K on a job you expect to cost $1M, you're 60% complete. Earned revenue is that percentage applied to the contract price — 60% of a $1.3M contract is $780K of revenue you've earned, whether or not you've billed it.

Percentage of Completion, in Plain English

The percentage-of-completion method, governed by IRC §460, recognizes revenue as the work gets done rather than when the job finishes or when you get paid. It exists because a two-year commercial project would otherwise show huge losses in year one (all cost, no revenue) and a giant windfall in year two. Matching revenue to progress gives a truer picture — and it's required for most larger contractors.

There's an exception: the small contractor exemption lets contractors under a gross-receipts threshold, on shorter contracts, use simpler methods. Whether you qualify is a conversation worth having with your accountant, because the method you use changes your tax timing significantly.

Overbillings vs. Underbillings

This is the heart of the WIP report, and it's where the money hides. Compare what you've billed to what you've earned:

Overbilling (billings in excess of costs) means you've invoiced more than you've earned. It feels like profit — there's cash in the account — but it's really a liability. That money belongs to work you still have to perform. Front-loading billings is healthy for cash flow, but mistake it for profit and you'll spend money you owe to the job.

Underbilling (costs in excess of billings) is the opposite and more dangerous: you've done more work than you've billed. It's an asset on paper, but it means you're financing the project out of your own pocket. Chronic underbilling is one of the quietest ways a profitable-looking contractor runs out of cash.

How to Read a WIP Report Like a Surety

When a bonding agent or banker reads your WIP, they're looking for a few signals: Are your gross profit margins holding steady across jobs, or slipping as work progresses — a sign of profit fade, jobs quietly losing margin? Is there heavy underbilling straining cash? Are estimated costs being revised upward repeatedly, suggesting weak job costing up front? A clean, consistent WIP tells them you run a business you can predict — and predictability is exactly what earns bigger bonds and better terms.

Common WIP Mistakes That Cost Contractors

The most common errors we see: not updating estimated costs as jobs change, so percent-complete becomes fiction; leaving approved change orders out of the contract price; booking deposits as revenue; and building the schedule once a year for the CPA instead of monthly for yourself. A WIP schedule is a management tool first and a compliance document second. Run it every month and it will warn you about a bad job while you can still fix it.

Where This Connects

Your WIP is only as accurate as the job costing feeding it — garbage in, garbage out. And a strong, consistent WIP schedule is the single biggest lever on your bonding capacity. Getting all of this right is core to our construction accounting work.

If your WIP schedule is a once-a-year scramble instead of a monthly management tool — or you're not sure your revenue is being recognized correctly — let's talk. It's one of the first things we fix.