The NEC4 ECS (Engineering and Construction Subcontract) is the form a Contractor uses to let part of its works to a Subcontractor when it holds an NEC4 main contract. It mirrors the ECC's clause numbers, but the Contractor takes over the Project Manager's and Client's positions, and many of the periods are different.
If you know the ECC, the structure will feel familiar. What catches people out is how the two contracts connect, which is what this page concentrates on. For the wider range of forms, see NEC contract types.
How the role names change
| In the ECC | In the ECS |
|---|---|
| Client | Contractor |
| Project Manager | Contractor |
| Contractor | Subcontractor |
| Contract Data | Subcontract Data |
| Scope | Subcontract Scope |
| the works | the subcontract works |
| Completion Date | Subcontract Completion Date |
| Subcontractor | Subsubcontractor |
The Supervisor doesn't disappear. Tests can still involve the main contract Supervisor, and the Subcontract Data asks for the names of the main contract Client, Project Manager, Supervisor and Adjudicator so that everyone knows who is who.
Where the two contracts connect
A subcontract is a separate contract. The Subcontractor has no direct contract with the Client, so notices go to the Contractor. Even so, the ECS has several links upwards:
- Early warning meetings. Under 15.2, the Contractor can require the Subcontractor to attend a main contract meeting where the matter also affects the subcontract. The early warning guide for subcontractors follows a warning through the chain.
- Disputes. If the same matter is being disputed at both levels, the Contractor can bring the Subcontractor into the main contract adjudication, so that one Adjudicator decides both together. The Subcontract Data names the main contract Adjudicator for this purpose.
- Termination. The Contractor has a stated reason for ending the subcontract if its own main contract obligation to provide the works has been terminated (91.9, reason R23).
- Design rights. The right to use the Subcontractor's design extends to the Client as well as to the Contractor, unless the Subcontract Scope says otherwise.
The periods are its own
The default ECS periods are not the ECC's, as this sample of the unamended forms shows.
| Step | NEC4 ECC | NEC4 ECS |
|---|---|---|
| Notify a compensation event (61.3) | 8 weeks | 7 weeks |
| Quotation due (62.3) | 3 weeks | 2 weeks |
| Reply to a quotation (62.3) | 2 weeks | 4 weeks |
| Reply to a programme (31.3) | 2 weeks | 3 weeks |
| Payment after the assessment date (51.2) | 3 weeks | 4 weeks, or as the Subcontract Data states |
The difference gives the Contractor time to pass things up the chain. The back-to-back subcontracts guide walks through a full timeline.
Options
The ECS has five main Options: A, B, C, D and E. There is no management subcontract, so Option F has no ECS equivalent. The subcontract doesn't have to use the same main Option as the main contract. A Contractor on Option C can let a package on Option A, for instance, which leaves the package price fixed while the Contractor's own target stays open. The usual secondary Option letters are available with some differences, one being that X11 in the ECS deals with termination by the Contractor.
Checklist for the Contractor before issuing it
- Confirm the main contract is NEC4. If not, take advice, because references to the main contract may not work as intended.
- Fill in the main contract details in the Subcontract Data.
- Check the Subcontract Scope flows down what the main contract Scope requires, including constraints.
- Make sure Key Dates and the Subcontract Completion Date fit the Accepted Programme.
- Decide who in your team acts as "the Contractor" under the subcontract, and give them the time to reply.
- Think about whether any Z clause is really needed. If you need one to fix a particular risk, keep it narrow.
Checklist for the Subcontractor
- Diarise the seven-week period, not the eight weeks you may remember from the ECC.
- Send your notices to the Contractor, whoever you deal with on site.
- Ask for the relevant parts of the main contract, particularly anything that restricts your work.
- Read what "Subcontractor" means in NEC if you intend to subcontract further.
Under NEC3, the ECS also exists, with the older terms. Check periods in that form directly, since they are not the same in every place.
Related guides
- NEC Contract Types: Which Form Do You Need?
- NEC4 Engineering and Construction Short Contract (ECSC)
- NEC4 Engineering and Construction Short Subcontract (ECSS)
- NEC4 Professional Service Contract (PSC)
- How to Choose the Right NEC Contract
- NEC4 Engineering and Construction Contract (ECC)
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This guide is general information in our own words, not legal advice. Your contract and its Contract Data always govern. NEC, NEC3 and NEC4 are trade marks of Thomas Telford Ltd; Contract Status is not affiliated with or endorsed by NEC.