Build late-payment claims for UK public-sector subcontractors
A claim-builder weaponising the Procurement Act 2023 for SMEs in public-sector supply chains
Executive Summary
In a nutshell
A SaaS that helps UK SMEs and freelancers in public-sector supply chains turn the Procurement Act 2023's 30-day payment rule into actual cash. It ingests their invoices and contract metadata, tracks PPN-compliant deadlines per public contract, auto-generates Public Procurement Review Service (PPRS) and Small Business Commissioner (SBC) complaints when terms are breached, drafts evidence packs for the new Procurement Compliance Service and the central debarment register, and tracks the 2026 reform package (60-day cap, mandatory interest, expanded SBC enforcement powers consulted on 24 March 2026). Distinct from generic chasing tools (Chaser, Satago) and from private-B2B interest enforcers, this one is statute-specific to public procurement, where tier-3 suppliers are technically protected and almost nobody enforces.
The Story
Meet the user
Marcus runs a small electrical contracting firm in Bristol, eight people on the books. About 60% of his work flows down from a Tier-1 main contractor on a council framework. The contract notice cites the Procurement Act and the standard 30-day payment term. In practice, his last three invoices to the main contractor have averaged 71 days. He knows the Act technically protects him as a sub-sub. He has no idea who to complain to, what evidence the Public Procurement Review Service wants, or whether kicking up a fuss will cost him the next job. So he eats it, draws on his overdraft, and pays his lads on time anyway.
Then a quantity-surveyor mate sends him a link. He uploads his last six months of invoices from Xero, picks the contracts that flowed from public bodies, and the tool spits back: £18,400 in late-paid invoices, statutory interest owed, three PPRS-ready complaint packs already drafted with payment-history evidence, contract references, and the right gov.uk submission route. He fires the first one off the same evening. The Tier-1 pays the lot inside 14 days, plus the interest, without him needing a phone call.
Scores
How does this idea stack up?
7.3/10
UK gov spends c. £385bn through public contracts; "procurement act 2023" pulls 5,400/mo on LOW competition. Niche is narrower than private B2B but high-intent.
FSB Q1 2025: 70% of small firms hit by late payments. Specific public-sector "black hole" called out by FSB December 2025 report.
Standard stack plus Xero/QB APIs, statute-citation engine, PPRS/SBC submission formatting. Nothing exotic.
Procurement Act in force 24 Feb 2025, Section 69 commenced 1 Jan 2026, reform consultation announced 24 March 2026. Live legislative wave.
Tied to a specific statute. Reform extends the surface, but if PPRS adjudication matures into a slick gov.uk tool, vendor value compresses.
Moderate. Accounting integrations and dual evidence-pack templates take real work. Solo dev, 6 to 10 weeks.
Strongest
Timing
The Act, the central debarment register, the PPRS, the Fair Payment Code and the 2026 reform consultation all stacked into a 14-month window.
Watch out
Durability
The value depends on a regulatory regime that will keep moving, so the product needs to track it as a feature, not a bug.
Pain Point
The problem
“Small companies are missing out on billions of pounds in public sector contracts due to a 'black hole' of unanswered feedback and red tape.”
— Federation of Small Businesses, December 2025 report
The Procurement Act 2023 is unusual in UK statute, because it explicitly extends the 30-day payment rule down the supply chain via Section 73, including to sub-sub-contractors. In theory, a tier-3 supplier whose Tier-1 main contractor sits on their invoice can demand the protections. In practice, three things bite: the supplier doesn't know which of their customers actually count as a public-sector supply chain (the fact often lives buried in Tier-1's contract notice, not on the SME's invoice); the supplier has no template for a PPRS complaint, can't cite the Act precisely, and doesn't know payment-compliance-notice data exists for that contract; the supplier worries about retaliation, so they wait, then hit the 12-month SBC complaint window, then it's too late.
The combined effect, on the FSB's numbers, is that 70% of small firms experienced late payments in Q1 2025, the UK economy loses c. £11bn a year to it, and the public-sector slice is a documented sub-segment that nobody is selling a tool into.
The 2026 reform package, announced 24 March 2026, adds a 60-day statutory cap, mandatory statutory interest at 8% over base rate, a 30-day invoice-dispute window, and new SBC enforcement powers (financial penalties up to a percentage of turnover, a new adjudication function settling disputes out of court). The consultation runs through spring/summer 2026, with primary and secondary legislation expected late 2026 to early 2027. That is exactly the window in which a niche tool can land.
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