NEC4 Contract Data Explained

NEC4 Contract Data holds the facts that turn the standard clauses into your contract: who the parties are, which Options apply, the dates, the periods and the percentages. Part one is filled in by the Client and part two by the Contractor. If an entry is wrong or blank, a procedure in the contract can stop working as intended.

This page covers the NEC4 ECC, using the layout of the NEC4 forms, so check your own copy. The term itself is also in the Contract Data definition. For other edition changes, see the NEC4 contracts guide.

What each part holds

Part one follows the contract's section order, with optional statements placed in the section they belong to.

Section	Typical entries in part one
1 General	Conditions of contract, main Option and secondary Options; the works; the Client, Project Manager and Supervisor; where the Scope and Site Information are; boundaries of the site; language and law; the period for reply; early warning matters and meeting interval
2 Contractor's main responsibilities	Key Dates and their Conditions; forecast interval on Options C, D and E
3 Time	Starting date; access dates; revised programme interval; Completion Date; period for the first programme, if none is identified
4 Quality management	Period for the quality policy statement and plan; defects date; defect correction periods
5 Payment	Assessment interval; interest rate; a different payment period, if used; share ranges on Options C and D
6 Compensation events	Weather data place and details; additional compensation events for 60.1(21)
8 Liabilities and insurance	Additional liabilities and the insurance table
Resolving and avoiding disputes	Tribunal; Senior Representatives, or Board members under W3; Adjudicator and nominating body
Secondary Options	Details for each Option chosen, such as X7 rates or X16 retention

Part two is the Contractor's data.

Entry	Why it matters
The Contractor's details	Sets the address for communications
Fee percentage	One figure in NEC4 (11.2(10))
Working areas	Affects which costs are recoverable
Key persons	Replacing one needs acceptance (24.1)
Programme identified, if any	Decides whether a first programme is due
Activity Schedule or bill of quantities, and tendered total	Depends on the main Option
People Rates (Options A, B); rates for design and for manufacture and fabrication	Used when assessing compensation events
Equipment list, percentage adjustment and other rates	Used when pricing Equipment

How to complete it

1. Choose the Options first. Then remove or complete the sections they trigger, so nobody has to work out what's relevant.
2. Write dates as dates. An access date "to be confirmed" isn't an access date. If a date really isn't known, sort out how it will be fixed before the contract is let.
3. Name the documents exactly. Identify the Scope and Site Information by title, revision and date, as the contract relies on these entries to find them.
4. Choose periods deliberately. The period for reply, revised programme interval and early warning interval set the pace of the job, so choose them to suit its speed.
5. Use the exceptions. The period for reply can have exceptions for particular matters. Use them for items such as design reviews that genuinely need longer.
6. Check part two when it comes back. Read the Contractor's entries before award, as these become the contract's rates.

A worked example

A fictional water treatment job, with illustrative entries.

Entry as drafted	The problem	A better entry
Early warning meeting interval: "as required"	Sets no interval, so the contract's limit on the gap between meetings has nothing to apply to	"4 weeks"
Scope: "see tender documents"	Tender queries and superseded drawings may or may not be included	"Volume 2 Scope, revision C, dated 14 May, and drawing list at Appendix 3"
Weather place: blank	60.1(13) can't be applied without knowing where the measurement is taken	The named recording station and data source
Assessment interval: "monthly"	Usable, but the first assessment date still needs deciding at the start	"4 weeks" or "one month", plus an agreed first date

What changed from NEC3

• The layout encourages completion on screen, and optional statements now sit in their relevant sections.
• Electronic addresses for communications are included.
• The early warning meeting interval is added.
• Space is added for additional compensation events.
• The disputes section includes Senior Representatives or W3 Board members.
• Part two has one fee percentage, no overhead percentages, and People Rates on Options A and B.

Changes like these are why reusing an NEC3 Contract Data form is a bad idea. Moving from NEC3 to NEC4 has more on replacing templates.

Pre-issue checklist

• Each chosen Option's data is complete, and each Option not chosen is removed.
• Every name, address and electronic address is current.
• Dates fit together: access dates, starting date, Key Dates and Completion Date.
• The early warning matters are real project risks, not a copy from the last job.
• The Z clauses and the data don't contradict each other.
• The subcontract data lines up with the main contract's periods. See back-to-back subcontracts.

Related guides

• NEC4 Contracts: A Complete Guide
• Learning NEC4: What Your Team Needs to Know
• NEC4 Questions and Answers
• What Is NEC3?
• Proposed Instructions and Quotations in NEC4
• NEC4 Terminology Changes

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.