NEC4 Compensation Events and Early Warnings: The Process, Clause by Clause
Under the NEC4 Engineering and Construction Contract, change is handled through compensation events, and almost every step has a clock: eight weeks for the Contractor to notify, one week for the Project Manager to reply, three weeks to quote, two weeks to answer. Silence has consequences in both directions, because NEC4 turns a missed reply into a deemed acceptance once the other side gives notice. This guide follows one event from early warning to implementation, with the clause for each step, a timescale matrix and a worked example.
- Published
- Sources checked
- Reading time
- 14 min
- Written by
- Mirage Metrics team
Scope: the core clauses of the NEC4 ECC (June 2017, with the January 2019, October 2020 and January 2023 amendments). Main Option, secondary Options, Contract Data and Z clauses can change any period or rule cited here. The NEC text is copyright and is paraphrased, not reproduced; buy it from NEC. This is not legal advice on a specific contract.
Decision snapshot
- Best suited to
- Project Managers, contractors' commercial managers, quantity surveyors and document controllers administering an NEC4 ECC on either side.
- Inputs needed
- The contract (Contract Data, Options, Z clauses), the Early Warning Register, the communications log, PM instructions, the Accepted Programme and its revisions, site records and Defined Cost records.
- What can be automated
- Logging every notification with its date received, computing the next contractual date, flagging overdue replies and the date a deemed acceptance would take effect, cross-checking open CEs against the programme, assembling cost records.
- What requires human approval
- Whether an event is a compensation event, whether to notify or give notice of a failure, the content of each notice, the quotation, the delay assessment and the acceptance.
- When this approach is insufficient
- A contract under NEC3 or another family, heavy Z clause amendments to clauses 6 or 3, a dispute already referred to adjudication, or a question of entitlement under the governing law.
Who this guide is for
It is written for the people who keep an NEC4 project's notices moving: the Project Manager and their team, the Contractor's commercial manager and quantity surveyors, and the document controllers who log every communication. It assumes you know NEC's roles (Client, Project Manager, Supervisor, Contractor) and focuses on the mechanics of change.
It is not a guide to FIDIC, which handles claims through notices with its own periods; see the FIDIC Red Book notices and claims guide for that family. And it covers the ECC, not the other NEC4 contracts, whose clause numbers differ.
Early warning and compensation event: two separate acts
The most common confusion in NEC administration is between these two. An early warning is a risk management tool; a compensation event notification is the start of a change to the Prices or the dates. NEC's own Q&A says one cannot stand in for the other, and a compensation event can be notified without any early warning before it.
| Early warning | Compensation event notification | |
|---|---|---|
| Purpose | Raise a matter that could increase the Prices, delay Completion or a Key Date, or impair performance, so it can be avoided or reduced | Change the Prices, the Completion Date or a Key Date for an event the contract allocates to the Client |
| Who gives it | The Contractor or the Project Manager, to the other (15.1) | The PM, for its own instructions and communications (61.1); the Contractor, for other events (61.3) |
| When | As soon as either becomes aware of the matter | PM: at the time of the instruction. Contractor: within eight weeks of becoming aware that the event has happened |
| What follows | An entry in the Early Warning Register and, where needed, an early warning meeting | A reply, an instruction to submit quotations, a quotation and an assessment |
| Missing it | If an experienced contractor could have warned, the CE is assessed as if it had (61.5, 63.7) | For a Contractor-notified event, no change to the Prices or dates, unless an exception applies (61.3) |
Source: NEC101 Q&A; NEC, Links between key NEC processes; Fenwick Elliott, issue 75.
Early warnings and the Early Warning Register
Under clause 15.1 the Contractor and the Project Manager each give an early warning, by notifying the other, as soon as either becomes aware of a matter that could increase the total of the Prices, delay Completion, delay meeting a Key Date or impair the performance of the works in use. The Contractor may also warn of other matters that could increase its own costs. Only those two parties can notify an early warning.
The Early Warning Register (defined in 11.2(8)) lists the matters the Contract Data names for inclusion and every matter notified since, each with a description and how its effects are to be avoided or reduced. It replaced NEC3's Risk Register, and NEC3's risk reduction meetings became early warning meetings. The timetable in clause 15.2, as practitioners quote it:
- The Project Manager prepares the first Early Warning Register and issues it to the Contractor within one week of the starting date.
- The Project Manager instructs the Contractor to attend the first early warning meeting within two weeks of the starting date.
- Later meetings are held when either party instructs the other to attend, and in any case at no longer interval than the one in the Contract Data, until Completion of the whole of the works.
- After each meeting the Project Manager revises the register and reissues it within one week.
Why a missed early warning still costs money
If the Project Manager decides the Contractor did not give an early warning that an experienced contractor could have given, it says so in the instruction to submit quotations (61.5), and the compensation event is then assessed as if the warning had been given (63.7). The Contractor keeps its compensation event, but loses whatever an early warning would have saved.
Source: Battersby (2019), quoting 15.1 and 15.2; GMH Planning; NEC on the enforcement clauses.
The compensation events in clause 60.1
The NEC4 ECC lists 21 compensation events in clause 60.1, two more than NEC3 (NEC). Main Options B and D add events for mistakes in the bill of quantities, and some secondary Options add their own, such as X2 for a change in the law. The events met most often in practice:
| Clause | Event | Note |
|---|---|---|
| 60.1(1) | The PM gives an instruction changing the Scope | The most common source: NEC's own training puts the share of CEs coming from such instructions at around 90% |
| 60.1(2) | The Client does not give access to a part of the Site when the contract requires it | |
| 60.1(3) | The Client does not provide something it is to provide by the date shown on the Accepted Programme | |
| 60.1(4) | The PM gives an instruction to stop work | |
| 60.1(5) | The Client or Others do not work within the times on the Accepted Programme | |
| 60.1(6) | The PM or the Supervisor does not reply to a communication within the period the contract requires | Also the fallback when the PM ignores a CE notification and the Contractor sends no reminder |
| 60.1(12) | Physical conditions within the Site, other than weather, that an experienced contractor would have judged at the Contract Date to have such a small chance of occurring that allowing for them would have been unreasonable | Only the difference from what it would have been reasonable to allow for counts |
| 60.1(13) | A weather measurement, in a calendar month at the place stated in the Contract Data, that the weather data shows occurs on average less often than once in ten years | Weather below that level stays with the Contractor |
| 60.1(20) | The PM notifies that a quotation for a proposed instruction is not accepted | New in NEC4 |
| 60.1(21) | An additional compensation event stated in Contract Data part one | New in NEC4: the parties can add their own |
Source: NEC101 slides; NEC on physical conditions; Battersby (2019). Headings are paraphrased; read each event in your contract.
For physical conditions, clause 60.2 assumes the Contractor took into account the Site Information, publicly available information it refers to, what a visual inspection would show and what an experienced contractor could reasonably obtain; where the Site Information is ambiguous, clause 60.3 assumes the more favourable conditions.
Notifying a compensation event
- The Project Manager's own events. When an event arises from the PM or the Supervisor giving an instruction or notification, issuing a certificate or changing an earlier decision, the PM notifies the compensation event at the time of that communication (61.1), and the notification includes the instruction to submit quotations.
- Everything else. The Contractor notifies any other event it believes is a compensation event, which the PM has not notified (61.3).
- The eight-week bar. If the Contractor does not notify within eight weeks of becoming aware that the event has happened, the Prices, the Completion Date and the Key Dates are not changed, unless the event arises from one of the PM or Supervisor communications listed above (Fenwick Elliott, quoting the NEC4 text). A compensation event that is not time-barred can still be notified by either party up to the defects date.
- The PM's reply. Within one week, or a longer period the Contractor agrees for that notification, the PM replies (61.4). NEC4 adds a reason the PM can give for no change: the event was not notified within the contract's timescales.
- Silence. If the PM does not reply in time, the Contractor may notify that failure. If it continues for a further two weeks, the event is treated as accepted as a compensation event, with an instruction to submit quotations (NEC). The reminder is optional; without it, the PM's failure to reply is itself a compensation event under 60.1(6).
The time bar is as strict as it looks, which is why the exceptions matter. Gowling WLG reports an NEC3 case in the High Court of Northern Ireland where a contractor was held not to be time-barred because the employer should itself have notified the instructions concerned (Gowling WLG). The NEC4 wording of the exception is different from NEC3's, so read it in your own contract.
Quotations
A quotation states the proposed changes to the Prices and any delay to the Completion Date and Key Dates, with the details of the assessment. If the event changes the programme for the remaining work, it includes the alterations to the Accepted Programme (62.2). NEC's Q&A notes that those are extracts: accepting the quotation does not make them a new Accepted Programme.
- After discussing different ways of dealing with the event, the PM may instruct alternative quotations, and the Contractor may add its own (62.1).
- The Contractor submits within three weeks of the instruction, and the PM replies within two weeks of the submission (62.3). Both periods can be extended by agreement (62.5).
- The PM's reply accepts the quotation, instructs a revised quotation with its reasons, or notifies that it will make its own assessment.
- If the PM does not reply in time, the Contractor may notify the failure; two further weeks without a reply and the quotation is treated as accepted. Where several quotations were submitted, the notice says which one (62.6).
- New in NEC4, the PM can ask for a quotation for a proposed instruction before deciding to give it (65). The Contractor quotes within three weeks; a quotation the PM does not accept is itself a compensation event under 60.1(20).
Source: NEC on PM assessments; NEC on the enforcement clauses; NEC101 Q&A; Battersby (2019).
Assessment: dividing date, Defined Cost, delay
NEC4 assesses a compensation event by its effect on cost and time, not by the rates in the contract. The change to the Prices is the effect on the actual Defined Cost of work done by the dividing date, the forecast Defined Cost of work not yet done, and the resulting Fee (63.1). The dividing date is the date of the communication for an event arising from a PM or Supervisor communication, and otherwise the date the event was notified. If both parties agree, rates and lump sums can be used instead (63.2).
Delay to the Completion Date is the length of time by which planned Completion becomes later, because of the event, than shown on the Accepted Programme current at the dividing date (63.5). The January 2019 amendment rewrote the third paragraph of 63.5 so the assessment takes account of delay from the event already shown on that programme and of events between its date and the dividing date (NEC amendments, January 2019).
The PM makes its own assessment in four cases (64.1): no quotation in time; the PM decides the quotation is wrongly assessed and does not instruct a revision; the quotation lacks the required programme alterations; or the PM has not accepted the latest programme for one of the reasons the contract allows. With no Accepted Programme, the PM uses its own assessment of the programme for the remaining work (64.2). If the PM does not assess in time, the Contractor may notify, and two further weeks of silence make the Contractor's quotation accepted (64.4). Once implemented, an assessment is not revisited (66.3), except where it rested on a PM assumption that later proves wrong (61.6).
The Accepted Programme
Every delay assessment runs against the Accepted Programme, so the programme clauses are part of the compensation event process. A programme shows, among other things, the starting date, access dates, Key Dates, Completion Date and planned Completion, the order and timing of operations, float and time risk allowances, the dates information is needed, and a statement of how each operation will be done (31.2).
- The PM accepts a programme or gives its reasons for not accepting it within two weeks (31.3). The reasons are limited: the plans are not practicable, information is missing, the plans are unrealistic, or the programme does not comply with the Scope.
- New in NEC4: if the PM does not reply, the Contractor may notify the failure, and one further week of silence makes the programme accepted.
- Revised programmes go in when the PM instructs, when the Contractor chooses, and at no longer interval than the Contract Data states (32.2). NEC4 dropped the requirement to show implemented compensation events; all remaining work is shown, including unimplemented ones.
- Until the Contractor submits a first programme with the required information, the PM retains a quarter of the Price for Work Done to Date (50.5).
Source: Fenwick Elliott, issue 94; Battersby (2019); NEC on the enforcement clauses; GMH Planning.
The timescale matrix
The matrix below is the reference card behind a compensation event register. Build it once from your own contract and check every period against the Contract Data. Each communication takes effect when it is received, or when sent through the communication system the Scope specifies (13.2); each notice is issued separately (13.7); and where no other period is stated, a reply is due within the "period for reply" in the Contract Data (13.3).
| Step | Who | Period | Clause | If nobody acts |
|---|---|---|---|---|
| First Early Warning Register | PM | Within 1 week of the starting date | 15.2 | No deemed outcome; a missing register undermines every later 61.5 argument |
| First early warning meeting | PM instructs, both attend | Within 2 weeks of the starting date, then at the interval in the Contract Data | 15.2 | No deemed outcome |
| Contractor notifies a CE | Contractor | Within 8 weeks of becoming aware that the event has happened | 61.3 | Prices and dates not changed, unless the event arises from a PM or Supervisor communication |
| PM replies to the notification | PM | 1 week, or longer if the Contractor agrees for that notification | 61.4 | Contractor may notify the failure; 2 further weeks of silence and the event is accepted, with an instruction to quote |
| Contractor submits quotation | Contractor | 3 weeks from the instruction | 62.3, 62.5 | The PM may make its own assessment (64.1) |
| PM replies to the quotation | PM | 2 weeks from the submission | 62.3, 62.5 | Contractor may notify the failure; 2 further weeks of silence and the quotation is accepted (62.6) |
| PM's own assessment | PM | The period set by 64.3 (check your contract) | 64.3 | Contractor may notify the failure; 2 further weeks of silence and its quotation is accepted (64.4) |
| PM accepts or rejects a programme | PM | 2 weeks from submission | 31.3 | Contractor may notify the failure; 1 further week of silence and the programme is accepted |
| Quotation for a proposed instruction | Contractor | 3 weeks | 65.1 | Not accepted: a CE under 60.1(20) |
The deemed acceptance clauses only work if the other side gives notice of the failure. A Contractor that keeps a register but never sends those notices gives away the mechanism NEC4 built to keep the process moving; a Project Manager who ignores them finds quotations accepted by default.
Worked example: an obstruction in the ground
Illustrative example, invented figures: a buried slab on a utilities project
Assumptions, all invented for this example. An NEC4 ECC with the core clause periods unchanged by the Contract Data, no agreed extensions, and an Accepted Programme in place. The Site Information shows no buried structures in the area.
| When | What happens | Register action | Status |
|---|---|---|---|
| Week 0, Monday | Excavation for a pump chamber meets a buried concrete slab that the Site Information does not show | Early warning notified (15.1); PM adds it to the Early Warning Register | Notified |
| Week 0, Monday | Contractor notifies a compensation event under 60.1(12), as a separate notice (13.7) | 8-week bar met on day one; dividing date is this notification (63.1) | Notified |
| Week 0, Thursday | Early warning meeting: removal method agreed to limit delay | Register updated, reissued within a week | Logged |
| Week 1 | PM's reply to the notification is due (61.4). None arrives | Contractor notifies the PM's failure to reply | Reply overdue |
| Week 3 | Two further weeks pass with no reply | Event treated as accepted as a CE, with an instruction to submit quotations | Deemed accepted |
| Week 5 | Quotation built: Defined Cost of the work done since week 0, forecast cost of the rest, Fee; delay assessed against the Accepted Programme current at week 0 | Programme extracts attached to the quotation (62.2) | In review |
| Week 6 | Quotation submitted, three weeks after the deemed instruction | PM's reply due by week 8 | Submitted |
| Week 8 | PM accepts the quotation | CE implemented; it cannot be revisited later (66.3) | Implemented |
The fork to watch. Had the Contractor given only the early warning, nothing would have started the compensation event process, and from week 8 the eight-week bar would have closed it. The opposite mistake was available to the PM: letting the reply lapse, then the two weeks after the Contractor's notice, so that the event was accepted without the PM ever deciding whether the slab was a condition an experienced contractor should have allowed for.
Mistakes that cost time or money
- Wait and see. Leaving compensation events to the end of the project is the first mistake on NEC's own training list (NEC101).
- An early warning instead of a notification. It starts nothing; the eight weeks keep running.
- Notifying before the event has happened. A future risk is an early warning matter; the eight weeks run from becoming aware that the event has happened.
- The wrong Accepted Programme. Delay is assessed against the programme current at the dividing date, not the latest one.
- No reminder notices. Deemed acceptance under 61.4, 62.6, 64.4 and 31.3 depends on the other party being told of the failure.
- Expecting a quotation to update the programme. The extracts in a quotation do not become the Accepted Programme.
- Poor records. Defined Cost is actual cost: without contemporary records, the assessment becomes an argument.
- NEC3 habits. The register, the meetings, the 61.3 exceptions and the programme's deemed acceptance all changed in NEC4.
Source: NEC101 slides; NEC101 Q&A; NEC on the enforcement clauses.
What software can prepare, and what stays with people
Most of the work in NEC administration is logging and chasing: which instruction changed the Scope, when a notification was received, which reply is overdue and when a deemed acceptance would bite. That work can be prepared by software that reads the communications and keeps the register current. The decisions that create or lose entitlement cannot.
| Task | Who does it | What stays with a person |
|---|---|---|
| Find every instruction, notice and site record that mentions an event | Can be prepared by software | Decide whether the event is a compensation event at all |
| Log each notification with its date received and compute the next contractual date | Can be prepared by software | Confirm the period, which the Contract Data or an agreement may change |
| Flag a reply that is overdue, and the date a deemed acceptance would take effect | Can be prepared by software | Decide whether to send the notice of failure that triggers it |
| Cross-check outstanding CEs against the latest programme submission | Can be prepared by software | Decide what the programme should show |
| Assemble the Defined Cost records for a quotation | Can be prepared by software, checked by the commercial team | Build the forecast, the delay assessment and the quotation itself |
| Draft a notification from a template, citing the source documents | Can be prepared by software, reviewed line by line | Sign and send it: the notice is the company's act |
This is the boundary Mirage works to on construction documents: its agents read instructions and revisions, link each extracted date to the document it came from, and flag what needs a person, as they do on document consistency work at OCBM (OCBM case study). Mirage has not published an NEC4 deployment; the NEC4 contract administration page describes what a first one would involve.
Readiness checklist
Run it at the starting date, and again when the team or the contract changes.
- Main Option, secondary Options and Z clauses read for every change to clauses 1, 3 and 6
- Period for reply, early warning meeting interval and revised programme interval copied from the Contract Data
- Communication system in the Scope identified, and the rule for when a communication takes effect agreed internally
- First Early Warning Register issued within one week, first meeting held within two weeks
- Compensation event register with one line per event, its trigger date, notification date and next contractual date
- Every early warning that could become a compensation event also diarised for an eight-week check
- A named person who sends the notices of failure that trigger deemed acceptance
- Accepted Programme versions archived, so the one current at any dividing date can be found
- Defined Cost records coded to each compensation event from the day it is notified
- Weekly register review, reconciled against the communications log
Questions readers ask
No. NEC's own Q&A is explicit that an early warning notification cannot double up as a compensation event notification. They are separate clauses with separate purposes, and a Contractor that only gives an early warning has not started the compensation event process. Give both, as separate notices.
Under clause 61.3 the Contractor notifies an event it believes is a compensation event, which the Project Manager has not notified, within eight weeks of becoming aware that the event has happened. If it does not, the Prices, the Completion Date and the Key Dates are not changed. The bar does not apply where the event arises from the Project Manager or the Supervisor giving an instruction or notification, issuing a certificate or changing an earlier decision.
The Project Manager has one week to reply, or a longer period the Contractor agrees. If it does not, the Contractor may notify that failure, and if the failure continues for a further two weeks the event is treated as accepted as a compensation event, together with an instruction to submit quotations. If the Contractor sends no such notice, the failure to reply is itself a compensation event under 60.1(6).
Three weeks from the instruction to submit it, and the Project Manager then has two weeks to reply. Both periods can be extended by agreement before the reply is due. If the Project Manager does not reply in time, the same notice-and-two-weeks mechanism makes the quotation accepted.
The date that splits the assessment between Defined Cost already incurred and forecast cost. For a compensation event arising from a Project Manager or Supervisor communication, it is the date of that communication; otherwise it is the date the compensation event was notified. Delay to Completion is assessed against the Accepted Programme current at that date.
No. It describes how to organise notices, records and deadlines under the NEC4 ECC core clauses. Your Contract Data, your main and secondary Options and any Z clauses can change what applies, and whether an event gives a right to time or money is a question for your commercial team and, where the value justifies it, a lawyer who has read the contract.
Sources and scope
Checked on . Scope: core clauses of the NEC4 Engineering and Construction Contract with its 2019, 2020 and 2023 amendments. The NEC text is copyright and is not reproduced here; the sources are NEC's own publications and law firm or practitioner commentaries that describe it. Always read your own contract, including its Contract Data and Z clauses.
- NEC with Sharpe Pritchard, NEC101 Compensation events: questions and answers (2024): early warning is not a CE notification, the 61.3 trigger, notification up to the defects date, the optional reminder under 61.4 and 60.1(6), programme extracts in a quotation, 66.3, 11.2(8)
- NEC with Sharpe Pritchard, NEC101 Compensation events webinar slides (October 2024): share of CEs arising from instructions changing the Scope, 60.1(3), common mistakes
- NEC, Do what NEC4 ECC says or face the enforcement clauses (2023): deemed acceptance under 31.3, 61.4, 62.6, 64.4; retention under 50.5; 61.5 and 63.7
- NEC, When and why NEC project managers have to assess compensation events (2022): quotation periods (62.3, 62.5) and the four cases of the PM's own assessment (64.1)
- NEC, Links between key NEC processes (2019): early warnings (15.1), 61.5 and 63.7, revised programme intervals (32.2)
- NEC, Compensation events: an introduction for new NEC users (2024): 21 compensation events in 60.1
- NEC, Compensation events for physical conditions (2018): 60.1(12), 60.2 and 60.3
- J. Battersby, Updating from NEC3 to NEC4 (University of Hong Kong, 2019): clause wording for 13.2, 15.1, 15.2, 31.3, 60.1(20) and (21), 63.1 and 65
- Fenwick Elliott, Insight issue 75: NEC4 (2017): the NEC4 wording of 61.3 and its exceptions, 60.1(21)
- Fenwick Elliott, Insight issue 94: programmes under NEC (2022): programme contents (31.2), acceptance (31.3), delay to Completion (63.5), 64.2
- NEC, Detailed NEC4 amendments, January 2019: the rewritten third paragraph of 63.5
- GMH Planning, NEC4 ECC: detailed review of changes from NEC3: first Early Warning Register and meeting (15.2), reissue after meetings, 61.4 late notification reason, 32.1
- Gowling WLG, Can NEC3 compensation events be assessed by reference to... (2017): the Northern Ireland NEC3 case on the time bar
- NEC, Engineering and Construction Contract Option A (product page): copyright and where the contract is sold
This guide explains contract administration practice for educational purposes. It is not legal advice and does not replace a reading of your contract by a qualified professional.
Related on this site
- NEC4 contract administration: tracking every notification against its deadline
- FIDIC Red Book notices and claims: the other contract family, with its own periods
- NRM2 bill of quantities: how the bill behind a priced contract is measured
- Change order review: checking a change against the original scope
- Plan revision comparison: what changed between two drawing issues
Test it on a register you have already closed
Send us the communications and early warning register for one compensation event you have settled. We will show you the register lines, dates and source links our agents produce, so you can compare them with what your team tracked by hand.
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