The NEC payment timetable, counted from the assessment date
A surveyor moving from JCT to NEC keeps the same instinct about payment dates and applies it to a different calendar. The instinct is close enough to feel right and wrong by about a week, which on a payment deadline is the whole game.
QScope Team · 20 July 2026 · 7 min read
NEC does not have interim valuation dates. It has assessment dates. The amount due is assessed at each assessment date, and every payment deadline that matters is counted from it. Get the assessment date right and the rest follows. Treat it as if it were a JCT valuation date and the whole timetable shifts.
Where the assessment dates come from
The first assessment date is decided by the Project Manager near the start of the contract. After that, assessment dates fall at the end of each assessment interval stated in the Contract Data, and at other points the contract specifies, such as Completion. They are not something the contractor chooses by putting in an application, which is the first habit a JCT surveyor has to drop.
Two ways the dates are counted, and which one you are on
How the due date and final date are counted depends on whether Option Y(UK)2 is in the contract. On any NEC job used for construction operations in the United Kingdom it almost always is, because that is the option that makes the contract comply with the Construction Act.
| Basis | Payment becomes due | Final date for payment |
|---|---|---|
| Y(UK)2 | 7 days after the assessment date | 14 days after the due date |
| Core clause 51.2, no Y(UK)2 | Payment made within 3 weeks of the assessment date | |
Both routes land in roughly the same place, around three weeks after the assessment date. The error is not usually choosing the wrong route. It is assuming the payment is due on the assessment date itself, which is neither route, and which pulls the final date and the pay less deadline forward by about a week.
The habit that causes it
Under JCT the due date is seven days after the interim valuation date. A surveyor who has internalised that sometimes reads the NEC assessment date as the equivalent of the due date, rather than the equivalent of the valuation date. It is the valuation date equivalent. The due date still sits seven days later under Y(UK)2.
So the assessment date is not the due date. It is the date from which the due date is counted. Setting a system, or a diary, so that the due date equals the assessment date understates every downstream deadline by seven days.
Counting the days
The days are counted the way the Construction Act counts them, from the due date, in the manner the contract and the Act require. The valuation date, or here the assessment date, is the input, not the thing the deadlines hang off. Every statutory deadline hangs off the due date.
That single discipline, count from the due date and set the due date correctly from the assessment date, removes the most common NEC payment date error before it happens. The rest is arithmetic.
The check on any NEC assessment
- Is the assessment date the one the contract and the Project Manager fixed, not the date an application arrived?
- Is Option Y(UK)2 in the contract? If so, the payment is due seven days after the assessment date, not on it
- Is the final date fourteen days after the due date, or the period your Contract Data states?
- Does the pay less deadline sit against the correct final date, with room to spare?
NEC payment dates are not harder than JCT ones. They are counted from a different starting point with a different name, and almost every mistake comes from mapping the NEC name onto the wrong JCT one.
QScope counts the NEC timetable from the assessment date under Option Y(UK)2, so the due date, the final date for payment and the pay less deadline all fall where the contract puts them, not where JCT habit expects.