Quick answer: Most public sector onboarding processes are designed to protect the organisation, not to welcome a supplier. That's a legitimate instinct, but when the process runs for six to ten weeks, demands documentation you already hold, and provides no meaningful feedback, it functions as a barrier to entry. You lose suppliers before they've delivered a single contract.
The part nobody talks about in procurement strategy
Supplier development work tends to focus on the front end: market engagement, tender design, social value criteria, evaluation methodology. All of that matters. But there's a quiet problem sitting at the back end of the process that undermines everything you've built upstream.
A supplier wins a contract with you. They've been through the tender. They've passed selection stage. You've decided they're the right choice. And then you hand them an onboarding pack that reads like a legal indemnity exercise and takes longer to complete than some of the shorter contracts they'll actually deliver.
That is not a neutral administrative process. It is a signal about what it's like to do business with you.
What a problematic onboarding process looks like in practice
I've seen onboarding processes that require a supplier to submit their insurance certificates, bank details, and company registration information at least three separate times across different systems. I've seen processes where new suppliers wait six weeks for a purchase order number while the contract start date ticks past. I've seen portals that reject document uploads without explanation, helpdesk queues that go unanswered, and welcome packs that were last updated when the organisation still had a different name.
None of this is malicious. It's the result of onboarding being treated as an IT and finance function rather than a procurement responsibility. The procurement team wins the contract and then, in practice, walks away.
The supplier is left to navigate something that wasn't designed with them in mind.
Why smaller suppliers feel this most
A large supplier with a dedicated contracts team can absorb a difficult onboarding process. They have the resource to chase, to duplicate submissions, to wait. A smaller supplier, a social enterprise, an SME that just won their first public sector contract — they don't have that buffer.
They're trying to mobilise delivery, hire staff if needed, and sort their own supply chain. When they're also chasing you for a PO number and re-uploading the same bank mandate for the third time, the hidden cost of the contract starts to look uncomfortably high.
Some of them will absorb it and make a note not to bid for you again. Some will mention it to other businesses in their sector. A few will pull out of mobilisation entirely. None of this shows up in your procurement metrics.
What good onboarding looks like
It's not complicated. The fundamentals are: a single point of contact during onboarding, a clear written timeline with milestone dates, no request for information you already hold from the tender process, a functioning portal or a functional alternative if the portal doesn't work, and a realistic mobilisation period built into the contract from the start.
Some organisations have introduced a named contract mobilisation lead who sits between procurement and finance for the first eight to twelve weeks of a new contract. That single structural change dramatically reduces the number of onboarding failures. It also gives the supplier someone who will actually pick up the phone.
The Procurement Act dimension
The Procurement Act 2023 strengthens requirements around prompt payment and transparency, including the expectation that buyers are operating in ways that don't unnecessarily disadvantage SMEs and new market entrants. A dysfunctional onboarding process doesn't just create operational problems — it increasingly sits in tension with the spirit of what the Act is trying to achieve.
If you're making commitments in your procurement strategy about market diversity and SME access, and then running an onboarding process that disproportionately burdens smaller suppliers, those two things are in direct conflict. At some point someone will notice.
The reputational dimension
Markets are small. Suppliers talk. If your organisation is known — even informally — as one that's difficult to onboard with, that affects who decides to bid for you. Not dramatically, not overnight, but steadily. The suppliers with choices start to exercise them elsewhere.
You don't always see this directly. What you see is a shortlist that keeps containing the same established names, because the newer market entrants tried once and didn't come back.
Practical takeaway
Pull your last five new supplier onboarding cases and time them. From contract award to first valid purchase order: how long did it actually take? Talk to one or two of those suppliers and ask them what the experience was like. You don't need a formal review process. You just need to ask the question and be prepared for an honest answer. What you find will tell you whether your onboarding process is supporting your supplier market or quietly working against it.