Form of tender and contract signature
There is no UK acte d'engagement: the form of tender binds your offer and the signed contract or order form creates the deal. What to check before you sign.
Updated on September 5, 2026
United Kingdom procurement has no single document equivalent to the French acte d'engagement. Its job is split in two: the form of tender, by which a bidder formally offers to perform the work at the price stated, and the contract itself, signed by both parties after award, which turns that offer into a binding agreement.
How it works
The form of tender sits in the invitation to tender pack. It is usually a short template, completed on the buyer's e-tendering portal, in which you confirm the contract you are bidding for, the lots covered, the tender price (a lump sum, or a cross-reference to the pricing schedule or schedule of rates), the tender validity period, and that your offer is made without collusion. Many buyers pair it with a certificate of bona fide tender and a declaration on conflicts of interest. Under the Procurement Act 2023 the supplier's core details, ownership and exclusion-grounds declarations are held once on the Central Digital Platform rather than retyped in the tender.
Where a bid is made by a consortium, the form identifies every member and the lead partner, and the buyer will usually require joint and several liability. Subcontractors you intend to rely on are named in the tender, and for certain contracts the buyer must be told before they are changed.
The contract is not concluded by the form of tender. After the standstill period the buyer issues a letter of acceptance or the parties execute the contract, either as a simple contract or as a deed, which extends the limitation period from six to twelve years. Under a framework, a call-off is made by signing an order form. Electronic signature is accepted for both routes.
What it means for a bidder
Fill in the form with absolute care: the figure it carries is the figure you are held to. Check that it matches your pricing schedule exactly, and that VAT treatment is stated the way the buyer asked.
Check that the signatory has authority to bind the company. For a consortium, make sure every member has authorised the lead partner or signs in its own right.
Do not amend the template. Adding a qualification, a reservation or your own terms of business is the most common reason a UK tender is ruled non-compliant and set aside without being scored.
Example
A cleaning company bids for a district council contract to clean its leisure centres, worth about £320,000 over three years. It completes the form of tender on the council's portal with an annual price of £104,500, confirms a 90-day tender validity period and names one window-cleaning subcontractor. It is not asked to sign a contract at this stage; the council issues its assessment summary, observes standstill, then sends the contract for electronic signature.
Frequently asked questions
Do I have to sign anything when I submit?
Yes, but only the tender documents: the form of tender and the declarations. The contract is signed later, by the winning bidder alone.
How long am I bound by my tender?
For the tender validity period stated in the instructions to tenderers, typically 90 or 120 days. Withdrawing inside that window can cost you the bid bond, where one is required.
Can I correct a mistake after submitting?
Before the deadline, resubmit through the portal; the later version replaces the earlier one. Afterwards, a buyer may allow a genuine arithmetical error to be confirmed or withdrawn, but it may not let you improve the offer.