Over-billing / under-billing

Over-billing means a contractor has invoiced more than the work actually completed justifies; under-billing means completed work sits unbilled — both distort a company's real cash and profit position.

Direct answer

What causes overbilling and underbilling in construction?

Overbilling and underbilling arise when cumulative billings do not match earned revenue for the work completed. Overbilling means billings are ahead of earned revenue; underbilling means earned revenue is ahead of billings. Both can be caused by timing, inaccurate percent-complete or cost forecasts, missing costs, unapproved changes, or an SOV that does not match the work.

Operational completeness check

01

Current contract value

Reconcile the original contract and approved changes before calculating progress.

02

Complete cost record

Post actual costs and accrue known work or invoices that have not reached accounting yet.

03

Reliable forecast

Update estimated cost to complete rather than relying on the original estimate after conditions change.

04

Earned-versus-billed

Compare cumulative earned revenue with cumulative billings for each job, not only in aggregate.

05

Exception follow-up

Explain material variances through billing timing, change status, missing cost, or progress-assessment errors.

Sources and verification

Revenue-recognition policy and financial-statement presentation require accounting judgment. Use this as an operational reconciliation, not accounting advice.

Published July 21, 2026 · Sources verified August 4, 2026 · Research methodology

Over-billing feels good in the short term — cash comes in ahead of the work — but it's borrowing from a future pay app, and it can flag as a warning sign to sureties and lenders reviewing WIP schedules. Under-billing is the quieter problem: the work is done, the crew's been paid, but the invoice hasn't caught up, so the company looks less profitable than it is and burns cash it's actually owed.

Both come from the same root cause — billing that isn't tightly tied to a schedule of values or a real percent-complete measurement, so what gets invoiced drifts from what actually happened on-site.

Example

A GC bills 90% on a job that's honestly 75% complete, to smooth out cash flow on a slow month. When the real percent-complete catches up, there's a billing gap for the last stretch of work with no room left on the contract to bill it.

Related terms

WIP reportA work-in-progress (WIP) report compares billed-to-date against earned revenue on every active job, surfacing over- or under-billing before it distorts a company's cash position.Job costingJob costing is tracking actual labor, material, and overhead costs against the estimate for a specific project in real time, so you know whether it's making or losing money before it closes out.Schedule of values (SOV)A schedule of values (SOV) is the cost breakdown of a contract by line item — the basis every progress payment is measured against, showing percent complete per item.

Next step

Where this shows up in Datumel:

Job-Costing Workbook InstallFrom $6,000 one-time

A configured job-costing workbook in your own Sheets or Airtable: cost codes, estimate-versus-actual, WIP, and over/under billing, with training to run it.

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