What is the NEC4 payment timeline?
Assessment date, due date seven days later, the Project Manager's certificate within one week of the assessment date, Pay Less Notice at least seven days before the final date, final date fourteen days after the due date, on an unamended NEC4 ECC with Y(UK)2.
Updated: 15 September 2026. By Jack Butler-Kettle, Quantity Surveyor & Claims Consultant.
The answer
NEC4 runs on assessment dates rather than applications. The first assessment date is set in the Contract Data and later ones follow at the assessment interval, with the Contractor entitled to submit an application before each. On an unamended NEC4 ECC incorporating secondary Option Y(UK)2, which applies the Construction Act, the Project Manager certifies payment within one week of the assessment date and that certificate is the Payment Notice, the due date is seven days after the assessment date, the final date for payment is fourteen days after the due date, and a Pay Less Notice must be given not later than seven days before the final date. Where no certificate is issued in time, the Contractor's application stands as the notice. Z clauses often amend these periods and the ECS subcontract form has its own, so as with JCT the executed contract governs the diary.
Example
The situation
An unamended NEC4 ECC with Y(UK)2 has an assessment date on the 25th of the month. A subcontract below it has Z clauses setting the final date for payment at 35 days after the due date.
What happens
- The certificate is due within the week of the assessment date.
- The due date is the 2nd of the following month.
- A Pay Less Notice must be given by the 9th, and the final date for payment is the 16th.
- Under the subcontract's Z clauses, the final date moves to the 6th of the month after and the Pay Less Notice deadline to the 30th.
The outcome
Under the unamended ECC the money is due on the 16th with a Pay Less Notice by the 9th; under the subcontract those dates become the 6th of the month after and the 30th.
Notice Deadline Tracking keeps the assessment dates and both notice windows in one diary.