Most of the firms I audit can tell me their turnover to the nearest thousand. Ask them how much they’re owed in retentions, and the answer comes in three parts. A pause. A guess. Then someone goes to find the spreadsheet.
If you’re not sure what a retention is, here’s the plain version. On most construction contracts the customer doesn’t pay you the full amount as you go. They keep back a slice of every payment — usually around five per cent, sometimes three on the bigger jobs — as a kind of security deposit. The idea is that if something you built turns out to be faulty, they’ve got your money in hand to make sure you come back and put it right. That held-back money is the retention. It’s yours. You’ve earned it. You just haven’t been given it yet.
How construction retention is released
The retention doesn’t come back in one go. It comes back in two.
The first half is released at practical completion — the point where the job is signed off as finished and usable, even if there are a few snags still to tidy up. The second half is released at the end of the defects liability period, also called the rectification period: a stretch of time, usually twelve months after practical completion, during which the customer can call you back to fix anything that has since gone wrong. When that period ends and any defects are made good, the rest of your money falls due.
So for every job there are two dates when money should land. One at completion. One a year or so later. And the second one is the problem.
Because a year is a long time. By then the job is finished, the team has moved on, the site manager is on something else, and the only record that you’re owed a few thousand pounds is a line in a spreadsheet nobody opens. The first half usually gets collected, because it’s close to the action. The second half is the one that quietly rots. I’ve sat with firms who had money still uncollected from jobs that finished two years earlier — the release date came and went, and nobody so much as sent an email.
Nobody decided to write that money off. It just fell through a gap that no one was watching.
Why retention release dates get lost
Here’s the root of it. Everything you need to collect a retention is real, specific and knowable on the day the job completes. The contract. The percentage held. The practical completion date. The length of the rectification period. The date the final half falls due. None of that is a mystery.
But it ends up in the wrong place. It lives in the quantity surveyor’s head, or in a tab of a spreadsheet that gets updated when someone remembers, or in the contract itself — a PDF in a folder that nobody is going to reread a year later to check a release date. The knowledge exists. It’s just nowhere that will ever prompt you to act on it.
And a retention only comes back if something prompts you to ask for it. No customer rings up to say your defects period ended last Tuesday and would you like your money now. You have to go and get it. If nothing reminds you, you don’t.
Will the retentions ban release your money?
There’s a fair chance you’ve read that retentions are on the way out. In March 2026 the government published its response to a consultation on late payment and said it intends to legislate to ban the practice of holding retention money on construction contracts altogether. That’s a real signal, and it points one way.
But read the small print. It’s a stated intention, not a law. The government has said it will consult further on how a ban would actually work before any final decision is taken. These things move in years, not weeks. And when it does land, it won’t reach back and release the retentions already being held against your finished jobs, or the contracts you’ll sign between now and then. Those run on the old terms.
So the money you’re owed today is still owed on the old basis, and still depends on you chasing it. Waiting for the law to fix a habit is a good way to leave money on the table for another three years.
What actually fixes it
This is not a job for a big platform. It’s a job for a list that pays attention.
What you want is a single register of every retention held against you. Each line knows the contract, the customer, the amount, the practical completion date and the length of the rectification period — and from those it works out the two dates the money falls due. Then it does the one thing a spreadsheet won’t: it tells you, before each release date arrives, that it’s coming and who to invoice. Not a report you have to remember to run. A prompt that comes to you.
That’s a small piece of software. It’s close to the simplest thing I build. But it’s shaped around the one question that matters — what are we owed, and when do we ask for it — rather than being a feature buried three menus deep in something you bought for another reason and never switched on. The whole value is that it nags. A spreadsheet doesn’t nag.
Where this doesn’t apply
If you’re mostly the one holding retention — a main contractor keeping money back from your subcontractors rather than having it kept from you — then your incentive runs the other way and this isn’t your problem to solve. If your jobs are few and small and you already collect both halves cleanly, a register is overkill; keep doing what works. And if you don’t work on standard contracts with retention clauses at all, none of this is about you.
But if you’re a mid-sized firm running a dozen or more contracts at a time, with retentions held against most of them, and you can’t tell me right now what you’re owed and when it’s due — the money is real, and some of it is probably already late.
If you want to find out how much, get in touch.
