Smash-and-grab adjudication: when a missed notice means they owe the lot

Published 23 July 2026 · VariationFlow

A plain-English guide to smash and grab adjudication for UK subcontractors: how a missed payment or pay less notice makes the notified sum payable in full, what the adjudicator actually decides, what S&T v Grove said about paying first, when to fire one, and when not to.

Your application said £142,000. No payment notice arrived within five days of the due date. No pay less notice arrived either. Then the final date for payment came and went, and £68,000 landed in the account with a spreadsheet attached explaining the difference. Here is the part many subcontractors still don’t believe until it happens: on those facts, the argument about what the work was worth may not matter yet. If the notices didn’t come, the sum in your application became the notified sum, and the notified sum is payable in full.

What is a smash-and-grab adjudication?

A smash-and-grab is an adjudication that enforces the notice regime rather than valuing the works. Under section 111 of the Construction Act, the payer must pay the notified sum for a payment cycle by the final date for payment unless it served a valid payment notice or pay less notice in time. Where it served neither, a properly made application for payment can itself stand as the notified sum. The adjudicator in a smash-and-grab decides a narrow set of questions: was the application valid, were the notices served in time, was the money paid? What the work was actually worth is not one of them.

What has to be true for it to work

• A valid application: made at the right time under the contract’s payment cycle, clearly stating the sum applied for and the basis of calculation, and recognisable in substance as an application for payment, not a spreadsheet ambush buried in an email thread.
• The dates counted correctly: the due date, the window for the payer’s payment notice, the prescribed period for a pay less notice, and the final date for payment. One miscounted date sinks the referral.
• No valid payer notice: late is invalid, a bare figure with no basis can be invalid, and a notice from the wrong entity is vulnerable.
• Service you can prove: how and when the application was sent, per the contract’s notices clause.

S&T v Grove: pay first, argue second

The payer’s standard response used to be “we’ll just adjudicate the true value and set one off against the other”. The Court of Appeal closed that route in S&T (UK) Ltd v Grove Developments: the payer must pay the notified sum first, and only after paying can it start its own “true value” adjudication to argue what the account is really worth. So a smash-and-grab gets the cash moving now; the valuation argument, if the payer wants one, happens with your money in your bank rather than theirs.

The honest caveats

• The money may not be final: a later true-value adjudication can claw some of it back. If your application was genuinely optimistic, expect that second round.
• It costs money: adjudicators’ fees and your own representation, proportionate on five and six-figure sums, harder to justify on small ones (though low-value schemes exist).
• It spends relationship capital: firing one at a contractor you want a pipeline from is a commercial decision, not just a legal one. Sometimes the letter before action does the whole job.
• Timing matters: take advice before referring, the right cycle, the right sum and clean facts win these; scrappy facts lose them.

The playbook when the notices didn’t come

• Diarise every final date for payment, every cycle, on every job: you cannot spot a missed notice if you don’t know when it was due.
• Check the payer’s paperwork against the clock the moment it arrives: on time? itemised? from the right entity?
• When a window closes with nothing served, put it in writing immediately: the notified sum, the missed notice, the final date, and that you expect payment in full.
• If the final date passes unpaid, escalate on a timetable: statement of account, letter before action, then the referral. Adjudication runs on a 28-day clock once it starts.
• Enforcement is the backstop: adjudicators’ decisions are enforced by the courts robustly and quickly, payers know this, which is why most pay before it gets there.

None of this works without the boring discipline underneath: applications submitted cleanly every cycle, dates tracked to the day, and the paper trail intact months later. That is exactly what VariationFlow’s payment timeline does, it diarises the due date, the pay-less window and the final date for every valuation, and when a window closes with nothing served it flags the possible notified sum, with the caveat that periods are contract-specific and worth verifying against your executed terms. This guide is general information, not legal advice: for a live dispute, involve a construction solicitor or claims consultant early, smash-and-grabs are won on clean facts and lost on scrappy ones.