RA Bill Retention and Release: A Construction Project Finance Control Guide

On a running account bill in construction, retention is a percentage — commonly 5% or 10% — withheld by the client from each certified amount as security against defects and completion. The contractor has earned the money; they just cannot draw it yet. Every RA bill certifies work, deducts retention, and pays the balance, so retention accumulates as a growing pool of the contractor’s own earned cash held by the client.

This retained amount is substantial. A few percent of every bill across the life of a large project adds up to a significant sum — often comparable to the project’s margin. Whether that money comes back on time, in full, is frequently the difference between a project that was profitable in reality and one that only looked profitable on paper while the retained cash sat unclaimed.

Because retention is earned-but-withheld money governed by contract rules and released on milestones, controlling it is a finance discipline: knowing how much is retained, where, and when it can be claimed back. Lose track of that and you have financed the client with your own margin.

Retention is not released all at once. Typically a first portion is released at practical completion — the work is done, so part of the security is no longer needed — and the balance is released after the defect liability period (DLP), the window after completion during which the contractor remains responsible for rectifying defects. Once the DLP ends without outstanding defects, the remaining retention falls due.

The exact percentages, the split between completion and DLP release, and the length of the DLP all vary by contract. One project might release half at completion and half after a twelve-month DLP; another might differ on every term. So retention release is not a single rule but a set of contract-specific triggers that each project carries, and tracking it means tracking those triggers per contract.

The release events are also easy to miss, because they happen long after the work — months after completion, at the end of a DLP that nobody is watching. A release that falls due and is not claimed is simply earned cash left with the client, and on a spreadsheet those dates slip through regularly.

Most contractors track retention in a spreadsheet, and across many RA bills, contracts and projects it is quietly wrong. Retention deducted on each bill is summed by hand; release dates are noted somewhere and forgotten; the balance per project drifts from reality as bills and corrections accumulate; and a release that should have been claimed passes unnoticed because nobody was watching that DLP end date.

The failure is not carelessness; it is that retention is a per-bill, per-contract, time-triggered position, and a spreadsheet is a poor tool for all three. Getting the deduction right on every bill, applying each contract’s specific terms, and surfacing a release date months in the future is exactly the kind of tracking spreadsheets do badly and lose silently.

The cost of the errors is real cash. Under-deduct and the security is wrong; miscalculate the balance and the project cash position is overstated; miss a release and the money stays with the client. Because retention is often close to the margin, these are not rounding errors — they are the difference the project was supposed to make, leaking through a tracking method that cannot keep up.

A construction ERP handles retention as part of RA billing, correctly and automatically. Each RA bill applies the contract’s retention percentage to the certified amount, so the deduction is right on every bill by construction. The retained balance is tracked per project and per client as bills accumulate, so the current retention position is always known rather than summed by hand. And the release triggers — practical completion, DLP end — are held against the contract, so the system flags each release as it falls due.

This turns retention from a drifting spreadsheet figure into a live, correct finance position. At any point you can see how much is retained across the portfolio, by project and client, and what is due for release and when — the information a finance function needs to claim retained cash on time and to understand the true project cash position.

It also makes retention claimable on time. Because the DLP end dates and completion milestones are in the system and flagged as they approach, the release is actioned when it falls due rather than discovered later, if at all. The earned-but-withheld cash comes back when it should, which is the whole point of tracking it.

Retention on RA bills is earned cash withheld as security, released in stages on contract-specific triggers, and on most projects it is tracked in a spreadsheet that quietly loses money — through wrong deductions, drifting balances and missed releases. A construction ERP applies retention correctly on every bill, tracks the retained balance per project and client, and flags releases at completion and DLP end, so the retained cash is visible and claimed on time. Because retention is often close to the project margin, controlling it is controlling whether the project actually makes what it was supposed to.

The discipline is finance, not admin: retention is a real, large, moving cash position that deserves to be managed as one. MBook builds India-first RA billing with retention, DLP, release tracking, advances and the rest of the commercial controls into a construction ERP, alongside the measurement book, BOQ and subcontract billing — so retained cash is tracked and claimed as part of the project’s finances rather than in a spreadsheet beside them. The test is whether you can state, right now, your total retention held and what is due for release this quarter; if that takes a spreadsheet rebuild, retention is leaking.