NEC Key Dates are dates by which part of the work has to reach a stated Condition, usually so that someone else can start. Each pairs a date with a Condition in the Contract Data, and the Contractor's duty is at clause 30.3. If one is missed and the Client has extra cost as a result, the Contractor pays that cost under 25.3.
They have the same structure in NEC3 ECC and NEC4 ECC. They differ from Completion: a Key Date doesn't require the work to be finished, or the works to be handed over. This page sits under the NEC programme guide, with a shorter Key Date definition for reference.
Key Date, section or Completion?
| Key Date | Section under Option X5 | Completion of the whole | |
|---|---|---|---|
| What it's for | An interface or milestone | A distinct part the Client wants finished by a date | The whole of the works |
| What is tested | The Condition stated | Completion of that section | Completion |
| Who certifies? | No certificate process in the clause | Project Manager | Project Manager |
| Consequence if late | Actual extra cost to the Client (25.3) | Delay damages per section, if X7 is used | Delay damages, if X7 is used |
| Take over | None | Yes, for the section | Yes |
The right tool depends on what the Client needs. Key Dates suit interfaces. The sectional completion guide covers parts that need to be finished and taken over.
What missing one costs
Clause 25.3 is narrower than people often assume. The Project Manager first decides that the Condition wasn't met by the date. Then the question is whether the Client has incurred additional cost, whether on its own work or in paying more to others on the same project, as a result. If so, the Contractor pays it.
- It isn't a daily rate. It is actual cost, not preset damages. If no extra cost arises, there is nothing to pay.
- It is the Client's only right for this failure, under the wording of 25.3.
- There is a time limit on the assessment. In NEC3 ECC, the Project Manager assesses within four weeks of the Condition being met. Under NEC4 ECS, it is five weeks for the Contractor. Check the period in your own contract for the NEC4 ECC.
- Payment comes through the amount due in the usual way.
A worked example
A fictional station upgrade, with illustrative figures. A Key Date requires the roof over Platform 2 to be watertight by 12 May, with a Condition that lets the Client's separate signalling contractor start inside. The Contractor meets the Condition on 2 June, three weeks late.
The signalling contractor was already mobilised and is entitled to an extra £31,500 from the Client under its own contract. The Client also pays £6,000 to re-book a possession. The Project Manager assesses £37,500. The Contractor pays this, whatever daily rate might be in Option X7, because this isn't a delay damages calculation. If the signalling contractor had itself been late and lost nothing, the Client's additional cost could have been nil.
How Key Dates change
- By instruction. The Project Manager can change a Key Date by instruction under 14.3, and that is a compensation event under 60.1(4).
- Through a compensation event's assessment. A delay to a Key Date is measured from the planned date for meeting the Condition on the Accepted Programme (NEC4 63.5; NEC3 63.3).
- By acceleration. A quotation under clause 36 can include changes to Key Dates: see acceleration under NEC.
- By correcting the description. Under NEC4 wording at 63.11 of the ECS, a Scope change that makes the Condition's description wrong is corrected as part of assessing that event. Check the ECC clause in your contract.
Each Key Date should also appear on the programme with a planned date, as 31.2 requires. A difference between planned date and Key Date behaves like terminal float, with the same logic for delay.
Writing a Condition that works
| Weak | Better |
|---|---|
| "Bridge deck complete" | "Deck waterproofing complete and accepted by the Supervisor, with safe access for the Client's lighting contractor" |
| "Handover of substation" | "Building watertight, floor screed cured, and the door keys passed to the Client's electrical installer" |
Good Conditions state what someone can see and test, and link to the reason for the date. Use them sparingly: every Key Date adds things to track. Keep them for interfaces that really cost money if missed. Early warnings also cover them: a risk of delay to a Key Date is a matter to notify under NEC4 15.1 (NEC3 16.1). The guide to what should be an early warning gives further examples.
Related guides
- The NEC Programme: A Complete Guide
- Sectional Completion
- Access Dates and Starting Work
- Acceleration Under NEC
- Completion Date and Planned Completion
- What Counts as Completion?
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