Procurement Act 2023 guidance documents - Procure phase · first published 1 July 2024
This guidance explains the rules in section 31 of the Procurement Act 2023 about modifying a live competitive procurement — that is, changing anything in a tender notice or associated tender documents after the process has started. Under the old rules, there was no specific legal provision for mid-process changes; the Act now fills that gap. Before suppliers have submitted tenders or requests to participate, contracting authorities can make any change, but must republish updated documents and consider whether deadlines need extending. After initial submissions, changes in a competitive flexible procedure (a multi-stage process) are only allowed if they are 'non-substantial' — meaning they would not have changed which suppliers entered the race. Light touch contracts (used for certain social, health and education services) are treated more flexibly and can be modified even substantially at the later stage. This guidance is primarily aimed at contracting authorities, but it directly affects suppliers by defining the legal protections they have during a live bid.
WHO THIS APPLIES TO
THE ENKII VIEW
For SMEs, this is a meaningful protection: if a buyer makes a significant change to conditions of participation or award criteria after the field of bidders has been set, that change is legally 'substantial' and is not permitted in a standard competitive flexible procedure. This means a buyer cannot quietly shift the goalposts after seeing who applied. SMEs should also note that any modification must trigger a review of deadlines — so if a buyer does make a change, you are entitled to expect extra time to respond. The light touch contract exception is worth knowing: if you bid for health, social care or similar services, buyers have more latitude to change terms mid-process, so stay alert to updates.
1. Monitor the tender notice and your bidding portal for any modification notices throughout the process — particularly after the request-to-participate stage. If a modification is issued, check whether you have been given additional time and, if not, contact the contracting authority to ask whether deadlines have been revised as required by section 31(4).
All SMEs actively bidding in a competitive flexible procedure (multi-stage tender) — The Act requires the buyer to consider revising deadlines whenever a modification is made; a buyer who changes terms without extending time may be in breach of section 31(4). Knowing this gives you grounds to request more time.
2. If you receive a modification notice after you have already submitted a request to participate or initial tender, assess whether the change is 'substantial' — i.e., would it have changed who was invited in the first place? If you believe it is substantial, raise a formal clarification question or complaint to the contracting authority, citing section 31(2) of the Procurement Act 2023.
SMEs that have been shortlisted (participating suppliers) in a competitive flexible procedure — Substantial modifications after initial submissions are not permitted in standard competitive flexible procedures. The Act gives participating suppliers a legal basis to challenge such changes.
3. When bidding on light touch contracts, build in an expectation that terms may change materially even after the field of bidders has been set. Review modification notices carefully and reassess your bid before final tender submission.
SMEs bidding for light touch contracts (e.g. health, social care, education services) — The Act explicitly removes the 'no substantial modification' protection for light touch contracts, meaning buyers have wider latitude to change conditions of participation or award criteria at any stage.
4. When a modification is published before the initial submission deadline, re-read the updated tender notice and all revised documents before finalising your bid — even if the change seems minor. Confirm that the deadline has been extended if the modification is complex.
All SMEs at the point of receiving a modification notice in an open or competitive flexible procedure — Section 31(5) requires the buyer to republish or re-provide affected documents, and section 54(1)(d) requires them to factor in the nature and complexity of the change when setting any revised deadline. You are entitled to enough time to respond to the updated terms.
Every rule below quotes the official document verbatim.
Section 31 governs modifications to 'anything set out in a tender notice or associated tender documents, including any requirements of a competitive tendering procedure, conditions of participation or award criteria'. (All covered procurements under the Procurement Act 2023)
“anything set out in a tender notice or associated tender documents, including any requirements of a competitive tendering procedure, conditions of participation or award criteria”
In an open procedure, a contracting authority may make any changes to the terms before the deadline for submitting tenders. (Open procedure procurements, all values, all sectors)
“in an open procedure, changes are permitted before the deadline for submitting tenders”
In a competitive flexible procedure, changes are permitted before the deadline for submitting a request to participate, or — where no such request stage exists — before the deadline for the first or only tender. (Competitive flexible procedure procurements, all values, all sectors)
“in a competitive flexible procedure, changes are permitted: i. before the deadline for submitting a request to participate; or ii. where there has been no invitation to submit such requests, the deadline for submitting the first or only tender.”
After initial submissions in a competitive flexible procedure, modifications are only permitted before the final tender deadline and must not be 'substantial'. (Competitive flexible procedure, post-initial-submission stage, all values, all sectors (excluding light touch contracts))
“contracting authorities are permitted to make modifications prior to the deadline for submitting final tenders for assessment under section 19, but limits any changes to those that are not 'substantial'”
A modification is 'substantial' if it would permit non-participating suppliers to submit a tender, or if the contracting authority considers the change would have altered which suppliers became participating suppliers. (Competitive flexible procedure, post-initial-submission stage, all values, all sectors (excluding light touch contracts))
“A modification is 'substantial' if: a. it would permit suppliers that are not 'participating suppliers' to submit a tender; or b. the contracting authority considers that, had the modification been reflected in the tender notice or associated tender documents before a deadline referred in section 31(1)(b) had passed... one or more participating suppliers would not be a participating supplier; or one or more suppliers that are not participating suppliers would be a participating supplier.”
A 'participating supplier' is one that has submitted a request to participate or a tender and has not been excluded. (All competitive tendering procedures under the Procurement Act 2023)
“A participating supplier is a supplier that has submitted a request to participate in, or has submitted a tender as part of, the competitive tendering procedure, and has not been excluded.”
For procurements for a light touch contract, there is no restriction on substantial modifications after initial submissions — modifications at any stage are permitted. (Light touch contracts, all values, specific sectors (social, health, education and similar services))
“For procurements relating to the award of a light touch contract there are fewer restrictions on modifications after a contracting authority has received requests to participate or has received initial tenders. In contrast to other types of public contract, there is no requirement for a modification to not be substantial.”
When any modification is made, the contracting authority must consider whether tender deadlines and other time limits need to be revised to give suppliers sufficient time to respond to the change. (All covered procurements under the Procurement Act 2023)
“Section 31(4) requires that whenever a modification to the terms of a covered procurement is made, the contracting authority must consider whether any tender deadlines and other time limits need to be revised in order to provide additional time for suppliers to take the change into account.”
When revising deadlines after a modification, the contracting authority must have regard to the nature and complexity of the modification under section 54(1)(d). (All covered procurements under the Procurement Act 2023)
“section 54(1)(d) requires the contracting authority to have regard to the nature and complexity of any modification of the tender notice or any associated tender documents.”
The previous legislation did not make specific provision for modifications during a procurement; section 31 of the Procurement Act 2023 is a new legal framework filling that gap. (All covered procurements — comparison with pre-Act position)
“The previous legislation allows suppliers to request information before submitting their tender but does not make specific provision for modifications during a procurement.”
When a non-substantial modification is made after initial submissions in a competitive flexible procedure, the contracting authority must notify each participating supplier of the modification. (Competitive flexible procedure, post-initial-submission stage, non-substantial modifications)
“the contracting authority must notify each participating supplier, for example by writing to them or updating the tender notice, of the modification”
This briefing is enkii's interpretation of the official document — the official text always governs.
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