NEC4 amendments: what changed and when
NEC4 came out in June 2017. NEC has since published sets of amendments in January 2019, October 2020 and January 2023. The set that applies to you depends on the version your contract names, so check which one it is before relying on any point below.
What the January 2023 set changed
This summary follows NEC's own notice of the changes, in our own words. It is not a complete list, and the amendment schedules NEC publishes with each contract are the record.
| Change | Forms | In short |
|---|---|---|
| Option X29, climate change | Main contracts | Published on its own in July 2022, then brought into each relevant contract. Requirements go in the Scope, the supplier gives a climate change plan, and performance can carry financial incentives. |
| People working away from site | ECC, TSC, TSS and others | The Contract Data can name people working outside the Working Areas, such as from home, whose cost counts as Defined Cost under the full Schedule. The short Schedule treats people normally based in the Working Areas in a similar way. |
| Using the supplier's design | ECC, SC and others | The Client's right to use the design now clearly reaches documents prepared for the design. Subcontracts follow. |
| Adjudication under Option W2 | Contracts with Y(UK)2 | The Adjudicator now expressly decides the procedure and timetable. |
| Option X22, early contractor involvement | ECC | Changes to how Stage One works: events are judged against the notice to proceed to Stage Two, and there is now a route for the case where Stage Two does not go ahead. |
| Design liability | ECSC, ECSS | An optional limit to reasonable skill and care, with a professional indemnity requirement and a compensation event for correcting a Defect the Contractor is not liable for. |
| Correcting a Defect not at fault | PSSC | A new compensation event where the Consultant corrects a Defect it is not liable for, having used reasonable skill and care. |
| Total limit of liability | ECSC, ECSS, SSC, TSSC and others | An optional overall limit can be stated in the Contract Data. |
| Payment on termination | SSC | What the Supplier is paid after termination for the Purchaser's default or convenience now follows the other contracts. |
The 2019 and 2020 sets
We do not list these in full here. Two examples we have confirmed from the contract text: the January 2019 set touched clause 50.9 and the NEC4 subcontract's final assessment timing, and the PSSC's people rates are stated without the Fee. The October 2020 set included changes to Option X22.
What to do about it
- Check the version named in your Contract Data before you rely on a clause number or a period.
- On a framework or a long job, check which version each call-off uses, as they can differ.
- If a Z clause already deals with the same point, read the two together.
More on the move between editions: moving from NEC3 to NEC4 and NEC3 vs NEC4. Then try the NEC4 ECC quiz, or the clause index.
General information in our own words, not legal advice. Your own contract, its Contract Data and any Z clauses decide.