Bidding for public sector work
for the first time.
The Procurement Act 2023 changed how this works in February 2025, and one requirement is absolute: register on the Central Digital Platform or you cannot be awarded a contract at all.
Published ·4 min read·Written by Unibuild
Register on the Central Digital Platform through Find a Tender before anything else: a public contract cannot be awarded to a supplier that is not registered on it. The Procurement Act 2023 applies to procurements commenced on or after 24 February 2025, and a good deal of the guidance still circulating describes the regime it replaced.
Register first, or nothing else matters
This is a hard gate and it is the one a first-time bidder is most likely to fail without realising.
The Central Digital Platform went live within the Find a Tender service on 24 February 2025. Suppliers register once, enter their core organisation details, and reuse them across bids rather than retyping the same information into every procurement. Existing Find a Tender registrations did not carry over: firms already on the old service had to register again on the new platform.
The part that matters commercially is that registration is a precondition of award. A contracting authority cannot award a public contract to a supplier that is not registered, which means an unregistered firm can write an excellent bid and still not be capable of winning it.
The best bid in the pile cannot be awarded to a supplier who is not on the platform. Do the registration on a quiet afternoon, not the week a tender closes.
What changed in February 2025
Enough that pre-2025 guidance should be treated with suspicion. The regime is more transparent by design, with more information published at more stages, and the practical effects on a bidder are worth knowing.
Core supplier information is held centrally and reused, which reduces the repetitive part of bidding considerably once you are set up. More notices are published across the life of a procurement, including at award and during contract performance, so there is more visible information about who is winning what. And there is more emphasis on assessing suppliers on past performance, which cuts both ways: a good delivery record becomes an asset, and a poor one becomes visible.
Finding the work
Find a Tender is the central service for higher-value public procurement and is where the notices you care about are published. Contracts Finder continues to carry lower-value opportunities. Many authorities also use their own portals, and a good deal of construction work reaches the market through frameworks rather than through individual notices.
The practical advice for a first-time bidder is narrower than "watch the portals". Pick two or three authorities within your geography whose work matches what you actually do, and follow those, rather than monitoring everything and pricing whatever appears. Public work rewards firms that understand a particular buyer, and pricing a random notice against people who have delivered for that authority for years is not a good use of estimating time.
Frameworks and dynamic markets
Most construction work for public bodies of any size is let through frameworks rather than one-off tenders, and understanding that changes where you spend effort.
A framework is a pre-competed arrangement: you compete once to get on it, then compete or are allocated work within it for its duration. Getting appointed is the significant event; individual call-offs are usually a lighter process. Which means the framework competition is where your effort belongs, and missing one can put you outside a buyer for several years.
Being on a framework is not a guarantee of work, which is the disappointment firms most often report. Some are heavily used and some are barely used, and asking about historic call-off volumes before investing in a bid is a reasonable and rarely-asked question.
Whether it is worth it
An honest answer, because public work suits some contractors and not others.
In favour: the buyer generally pays, which after everything on this site about payment risk is not a small consideration. Frameworks give visibility of forward work. Payment terms are often better than main contractor terms, and there are public sector prompt payment expectations that flow down the chain.
Against: the bidding cost is real and front-loaded, the compliance burden is heavier, the evidence requirements assume a level of documentation many smaller firms do not have ready, and the process is slow. A firm without current accreditation and a tidy compliance file will spend more getting ready than it expects.
The reasonable test is whether you can assemble the evidence pack described in getting on an approved list in a day. If yes, the marginal cost of a public bid is manageable. If assembling it is a project, do that first and bid afterwards.
Public bidding is an evidence exercise more than a writing exercise, and the questions are the ones this platform exists to answer: your health and safety record, accident and RIDDOR history, training and competence records, insurance currency, quality and environmental arrangements, and increasingly your past delivery performance with dates attached. Unibuild holds those against jobs and people with the dates they happened rather than as documents somebody assembles for a submission. It does not write bids, does not register you on anything, and will not tell you whether an opportunity is worth pricing.
Where to start, on Monday
Register on the Central Digital Platform through Find a Tender. It is administrative, it takes an afternoon, and it is a precondition of ever being awarded a public contract. Doing it now rather than during a live tender removes the worst version of this problem.
Then pick two authorities whose work genuinely matches yours, find out what frameworks they use and when those are next competed, and put those dates in the diary. Framework competitions are the events that matter and they come round rarely.
The follow-up questions.
The accreditation you will be asked for is mapped in SSIP, CHAS, Constructionline and what replaced PAS 91.
How do I bid for public sector construction work?+
What is the Central Digital Platform?+
Do I have to register to win public sector work?+
What is a framework and is being on one worth it?+
Is public sector work worth it for a smaller contractor?+
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