The NEC4 contract explained: how the ECC works, from the programme side
By Roman Bazelchuk | NEC Accredited Project Manager | APMG Project Planning and Control
Founder, NEC Planning Solutions Ltd
Checked against the NEC4 ECC, June 2017 edition with the amendments to January 2023 and the June 2026 X29 update.
The NEC4 contract is the fourth edition of the NEC suite, launched in June 2017. Its Engineering and Construction Contract (ECC) joins nine sections of core clauses to one main option, one dispute resolution option and the secondary options the Client chooses. Under it, delay is measured against one document: the Accepted Programme.
Many guides to the NEC4 contract are written by lawyers or quantity surveyors. Lawyers cover rights and quantity surveyors cover money. This one is written from the planning desk. It reads each part of the contract for what it asks of the programme and when, because under NEC that is where time is won or lost.
It is for contractors' commercial, planning and site teams meeting NEC4 for the first time. It also suits anyone who learned NEC3 and wants to know what moved. Project Managers on the Client's side will find their own deadlines here too.
Where a subject has its own full guide on this site, this page gives the outline and links to it. The six main options, programme acceptance under clause 31, the compensation event time bar and the dividing date each have one.
What the NEC4 contract is and where it sits in the NEC family
NEC is a family of standard contracts published by Thomas Telford Ltd, the commercial arm of the Institution of Civil Engineers. The fourth edition, NEC4, was launched on 22 June 2017. It replaced NEC3, first published in 2005 and updated across the suite in April 2013. NEC4 has had three sets of amendments, dated January 2019, October 2020 and January 2023. In June 2026 its climate option, X29, was widened to take in nature.
When people say "the NEC4 contract" or simply "the NEC contract", they usually mean the Engineering and Construction Contract, the ECC. It is the contract between a Client and a contractor for construction or engineering work. This page is about the ECC. The rest of the family covers the other relationships on a project. The Institution of Civil Engineers calls NEC3 and NEC4 the UK public sector's contracts of choice.
Table 1: The main contracts in the NEC4 family
Contract | What it is used for |
Engineering and Construction Contract (ECC) | Construction or engineering work between a Client and a contractor |
Engineering and Construction Subcontract (ECS) | The same terms passed from the contractor to a subcontractor |
Engineering and Construction Short Contract (ECSC) | Simpler work with lower risk and fewer procedures |
Professional Service Contract (PSC) | Design and consultancy, often including the Project Manager's own appointment |
Term Service Contract (TSC) | Maintenance and services delivered over a period rather than as a project |
Supply Contract (SC) | Goods and plant supplied to a Client |
Design Build and Operate Contract (DBO) | One supplier designs, builds and then operates an asset |
Alliance Contract (ALC) | Several parties working as one alliance with shared incentives |
Framework Contract (FC) | A framework under which individual contracts are called off |
Dispute Resolution Service Contract (DRSC) | Appointing an adjudicator or a Dispute Avoidance Board |
Hong Kong has its own edition of the ECC, launched by the Development Bureau in July 2023 and based on NEC4. What it changes for the programme is in the guide to Hong Kong NEC4 ECC programme compliance. How NEC grew into the family above is told in the history of NEC. Where a job runs on another form, JCT vs NEC vs FIDIC compares what each asks of the programme.
How an NEC4 contract is put together
An NEC4 ECC is assembled from parts. Every contract has the core clauses. To them the Client adds one main option and one dispute resolution option. The main option sets how the Contractor is paid. The Client then chooses any secondary options it wants from the X and Y(UK) clauses. Its own amendments go in as Z clauses.
The Contract Data, the schedule of details particular to the project, then fills in the blanks. Part one is the Client's: the dates, the periods, the chosen options and the documents that make up the Scope and the Site Information. Part two is the Contractor's: its key people, its fee percentage, its people rates and any programme it offers for identification in the Contract Data. The Accepted Programme is that programme until the Project Manager accepts a later one.
The Scope states what the Contractor has to do and any constraints on how it does it. It replaced NEC3's Works Information. The Site Information describes the Site and its surroundings. Compensation events are the events that can change the Prices, the Completion Date and the Key Dates. When one for physical conditions is assessed, the Contractor is assumed to have taken the Site Information into account, among other sources (60.2).
The nine core clause sections are the same whichever options are chosen. Read from the planning desk, most of them shape the programme.
Table 2: The nine core clause sections and what each does to the programme
Section | What it covers | What it does to the programme |
1 General | Actions, communications, early warnings, the Contractor's proposals | Sets the early warning routine (15) and the period for reply (13.3), the default time for answering a communication |
2 The Contractor's main responsibilities | Providing the Works, design, people, working with Others, subcontracting | Sets what the Contractor designs and how it works alongside Others. If the Client or Others miss the times on the Accepted Programme, that is a compensation event (60.1(5)) |
3 Time | Starting, Completion and Key Dates, the programme, access, take over, acceleration | The centre of it: the first programme, its acceptance and its revisions (31, 32) |
4 Quality management | The quality system, tests, inspections and Defects | Tests and inspections become activities. A test or inspection by the Supervisor that causes unnecessary delay is a compensation event (60.1(11)) |
5 Payment | Assessing the amount due, payment, Defined Cost | The amount due follows progress. Under Option A only completed activities are paid |
6 Compensation events | The events, notifying, quotations, assessing, implementing | Delay is measured against the Accepted Programme current at the dividing date (63.5) |
7 Title | Plant and Materials, Equipment and objects found on the Site | Rarely a programme matter. An instruction about an object of value or interest found on the Site is a compensation event (60.1(7)) |
8 Liabilities and insurance | Each party's liabilities and the insurances | An event the conditions of contract make a Client's liability is a compensation event (60.1(14)). Most are listed in 80.1 |
9 Termination | Reasons, procedures and payment on termination | The amount due on termination starts with the work done, assessed as for a normal payment, so the progress record matters |
The six main options in one table
The main option sets how the Contractor is paid and who carries the cost when the work costs more than planned. It is the central commercial choice in the contract. It also changes what the programme has to prove each month.
Table 3: The NEC4 main options
Option | How the Contractor is paid | Who carries an overrun | What it asks of the programme |
A Priced contract with activity schedule | The lump sum for each completed activity | The Contractor | Activities that match the programme's operations, since a part-complete activity earns nothing |
B Priced contract with bill of quantities | Completed quantities at the bill rates | The Contractor on its rates, the Client on quantities | Quantities, which are hard to show on a programme built from activities |
C Target contract with activity schedule | Defined Cost plus the Fee, with a share of any saving or overrun against the target | Shared, through the Contractor's share | A programme that supports the forecasts of Defined Cost (20.4), against a target that moves with each compensation event |
D Target contract with bill of quantities | As Option C, with the target from a bill of quantities | Shared | As Option C, with quantities |
E Cost reimbursable contract | Defined Cost plus the Fee | The Client | A programme that supports the forecasts of Defined Cost (20.4). With no target, the Client relies on them |
F Management contract | Defined Cost, mostly subcontract payments, plus the Fee | Mostly the Client | The sequence of the subcontract packages |
How each option pays and what it asks of the programme month by month is set out in the guide to NEC4 Options A to F. NEC4 Option A vs Option C sets the two activity schedule options side by side.
Secondary options that change time and money
Secondary options are chosen in Contract Data part one. Each adds clauses or changes existing ones. Some work only with certain main options, as the table shows. X12 and X20 cannot be used together. There is no X19 in the ECC.
Table 4: The NEC4 ECC secondary options
Option | Name | What it changes |
X1 | Price adjustment for inflation | The Prices move with an index. Options A to D only |
X2 | Changes in the law | A change in the law of the country where the Site is, made after the Contract Date, is a compensation event |
X3 | Multiple currencies | Payment in more than one currency. Options A and B only |
X4 | Ultimate holding company guarantee | A guarantee from the Contractor's ultimate parent |
X5 | Sectional Completion | A completion date for each section, each one a programme milestone |
X6 | Bonus for early Completion | A bonus for each day the works finish early |
X7 | Delay damages | Damages for each day from the Completion Date until the earliest of Completion, take over and the date of a termination certificate |
X8 | Undertakings to the Client or Others | Collateral undertakings to the Client and named Others |
X9 | Transfer of rights | The Client takes the Contractor's rights in material prepared for the design of the works, unless the Scope says otherwise |
X10 | Information modelling | Information model requirements and an information execution plan |
X11 | Termination by the Client | The Client may terminate the Contractor's obligation to Provide the Works for any reason |
X12 | Multiparty collaboration | Shared objectives with the Client's other suppliers. Not with X20 |
X13 | Performance bond | A bond for the Contractor's performance |
X14 | Advanced payment to the Contractor | Money paid early and repaid in instalments |
X15 | The Contractor's design | Design liability limited to reasonable skill and care |
X16 | Retention | Part of each payment held back. Not with Option F |
X17 | Low performance damages | Damages when the works fall short of a stated performance level |
X18 | Limitation of liability | Caps on the Contractor's liabilities |
X20 | Key Performance Indicators | Targets that are reported and can be rewarded. Not with X12 |
X21 | Whole life cost | Proposals that cut the cost of running the asset |
X22 | Early Contractor involvement | A two-stage process before construction. Options C and E only |
X29 | Climate change | Climate requirements stated in the Scope. The June 2026 version adds nature, so check which version the Contract Data selects |
Y(UK)1 | Project Bank Account | Payments to the supply chain through a project bank account |
Y(UK)2 | The Housing Grants, Construction and Regeneration Act 1996 | Payment notices and timings that meet the Act |
Y(UK)3 | The Contracts (Rights of Third Parties) Act 1999 | Which third parties can enforce a term |
A planner reading a new NEC4 contract checks five of these first, because each changes the programme or what it is worth. X5 adds a completion date for each section. X7 sets the delay damages per day, for the whole of the works and for each section. X6 pays a bonus for finishing early. X16 holds back part of each payment. Y(UK)2 sets when payment notices are due and so when the money the programme earns arrives.
Z clauses are the parties' own amendments. They are where a standard contract stops being standard, so read them before relying on anything in this guide. A Z clause that changes a period for reply, the programme clauses or the time bar can matter more than the standard wording.
Who does what under NEC4
NEC4 names its roles and gives each one deadlines. The Contractor's are the best known. The Project Manager's and the Supervisor's matter as much, because a late reply from either is a compensation event (60.1(6)).
Table 5: The roles under the NEC4 ECC
Role | What it does | Deadlines a planner watches |
Client | Gives access to the Site and provides what the Scope says it will, by the dates the contract and the Accepted Programme set. Appoints the Project Manager and the Supervisor | Late access or late provision is a compensation event (60.1(2), 60.1(3)) |
Contractor | Provides the Works in line with the Scope. Submits programmes, early warnings, compensation event notifications and quotations | First programme within the period in the Contract Data, notifications within eight weeks (61.3), quotations within three weeks (62.3) |
Project Manager | Manages the contract for the Client: instructions, acceptances, payment assessments and compensation events | Programme reply in two weeks (31.3), compensation event reply in one week (61.4), quotation reply in two weeks (62.3) |
Supervisor | Looks after quality: tests, inspections and Defects | Notifies a Defect as soon as it finds one (43.2) and issues the Defects Certificate |
Senior Representatives | Named by each party in the Contract Data. Meet to try to settle a dispute | The periods in the dispute resolution option |
Adjudicator or Dispute Avoidance Board | Decides disputes under W1 and W2. Under W3 the Board recommends. Appointed under the Dispute Resolution Service Contract | The periods in the dispute resolution option |
Two points catch out teams new to NEC. First, the Project Manager is appointed by the Client and acts for it, but only within the powers the contract gives it. Like the Parties and the Supervisor, it is bound to act in a spirit of mutual trust and co-operation. Some of its silences also count as decisions. Once the Contractor has notified the failure, silence on a programme (31.3), a compensation event notification (61.4) or a quotation for a compensation event (62.6) counts as acceptance. If the Project Manager owes an assessment and does not make it in time, the Contractor's quotation is treated as accepted two weeks after a failure notice (64.4).
Second, only the Project Manager can change the Scope. The Supervisor deals with quality and cannot decide time or money, though its tests and late replies can still be compensation events (60.1(6), 60.1(11)).
How time works: the programme is the contract's clock
Time under NEC4 hangs on a few dates in the Contract Data: the starting date, the access dates for each part of the Site, the Completion Date and any Key Dates, which are dates by which a stated condition must be met. The Contractor plans the work between them. The programme shows how. Once accepted, it is the yardstick for measuring delay.
The first programme
If no programme is identified in the Contract Data, the Contractor submits a first programme within the period the Contract Data states, counted from the Contract Date, not the starting date (31.1). Until it submits one showing the information the contract requires, a quarter of the Price for Work Done to Date is retained (50.5). That price is the value of the work done, on which each payment is built.
Clause 31.2 lists that information. The programme shows the contract's own dates and planned Completion, the date it forecasts for Completion. It shows when the Contractor plans to meet each Key Date condition and to finish work the Client and Others need. It sets out the order and timing of the work, including the work of the Client and Others. Float, time risk allowances, the health and safety requirements and the procedures the contract sets out go on it. A time risk allowance is the time the Contractor adds to an activity for the risks it carries.
The programme also shows the dates the Contractor needs acceptances, things the Client is to provide and information from Others. Where it needs access later than the access date, it shows that date too. For each operation it states how the work will be done and with what principal Equipment and other resources. The last item is any other information the Scope requires. NEC4 added one requirement of its own: the programme is in the form the Scope states. The detail is in what clause 31 requires for acceptance.
Acceptance in two weeks
The Project Manager has two weeks to accept a programme or give its reasons for not accepting it (31.3). The contract limits the reasons to four: the plans are not practicable, the programme lacks information the contract requires, it does not represent the Contractor's plans realistically or it does not comply with the Scope. If the Project Manager does neither, the Contractor can notify the failure. A further week of silence then counts as acceptance. NEC3 had no such step. Withholding acceptance for a reason the contract does not state is itself a compensation event (60.1(9)).
How much can turn on which programme was accepted is shown by Premier Modular v Maidstone. Both parties agreed that the only Accepted Programme was the original. The adjudicator decided the case on a later revision that neither party said was accepted, under a clause neither had relied on. The court refused to enforce the award, just over £1.65m, for breach of natural justice.
Revisions
Once accepted, a programme is the Accepted Programme until a later one is accepted. The Contractor submits a revised programme when it chooses to, within the period for reply when the Project Manager instructs one and in any case at intervals no longer than the Contract Data states (32.2).
Each revision shows the actual progress on each operation and its effect on the timing of the remaining work. It also shows how the Contractor plans to deal with delays and correct notified Defects, with any other changes it proposes to the Accepted Programme (32.1). NEC4 dropped NEC3's item on the effects of implemented compensation events, so a revision can show every compensation event, implemented or not. The detail is in what a clause 32 revision needs to show.
Early warnings
Early warnings run alongside the programme. The Contractor and the Project Manager each give one as soon as they become aware of anything that could add to the total of the Prices, delay Completion, delay meeting a Key Date or reduce how well the works perform in use (15.1). The Project Manager issues the first Early Warning Register, the list of those matters and the actions agreed on each, within one week of the starting date. Early warning meetings follow at intervals no longer than the Contract Data sets. If the Project Manager has notified that the Contractor did not give an early warning an experienced contractor could have given, the compensation event is assessed as if it had been given (63.7). The routine is set out in how to make the early warning register reduce delay.
Float and acceleration
Float follows from the assessment rules. Terminal float, the time between planned Completion and the Completion Date, stays with the Contractor, because a compensation event moves the Completion Date by its effect on planned Completion (63.5). Commentators treat time risk allowances as the Contractor's too, not as time the Project Manager can use. Both are explained in terminal float and time risk allowance.
Acceleration needs agreement. Either side may propose it. Nothing changes until the Project Manager accepts a quotation for it (36). How acceleration and mitigation work in practice is in the guide to programme acceleration and mitigation.
How money works
Under Options A and C the Prices are the lump sums in the activity schedule, the Contractor's priced list of activities. Under Options B and D they come from the bill of quantities. The Project Manager assesses the amount due at each assessment date. Its core is the Price for Work Done to Date.
Under Option A that is the total of the Prices for completed activities, so a part-complete activity earns nothing yet. Under Option B it is the completed quantities at the bill rates, plus the completed share of each lump sum item. Under Options C and D it is the Defined Cost the Project Manager forecasts will have been paid before the next assessment date, plus the Fee. Under Options C and D the total of the Prices is the target. It does not decide the monthly payment.
Defined Cost under Options C, D and E is the cost of the components in the Schedule of Cost Components, less Disallowed Cost. Disallowed Cost is cost the contract will not pay, such as cost not justified by the Contractor's accounts and records. Under Options A and B, compensation events are assessed with the Short Schedule of Cost Components. The Fee is the fee percentage the Contractor tendered, applied to Defined Cost. Defined Cost in NEC4 sets out what is included and what is disallowed.
Under Options C and D the Contractor's share of any saving or overrun is assessed provisionally at Completion of the whole of the works and finally in the final amount due, not month by month (54). Retention under X16 holds back part of each payment. Y(UK)2 brings the payment notices and timings of the Housing Grants, Construction and Regeneration Act 1996, the Construction Act, into the contract. How the programme drives all of this is in NEC4 cashflow.
How change works: compensation events
Compensation events are how NEC4 prices change. Clause 60.1 lists 21 of them. They include the Project Manager changing the Scope (60.1(1)), the Client not providing something by the date on the Accepted Programme (60.1(3)) and physical conditions an experienced contractor would have judged too unlikely to allow for (60.1(12)). Each is assessed for its effect on the Prices, the Completion Date and the Key Dates together.
Notifying within eight weeks
The Contractor notifies an event within eight weeks of becoming aware that it has happened. If it does not, the Prices, the Completion Date and the Key Dates do not change (61.3). 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 notifies those events itself (61.1).
Once the Contractor notifies an event, the Project Manager has one week to reply on whether it is a compensation event. If it stays silent, the Contractor can notify the failure. Two further weeks of silence count as acceptance that it is a compensation event and as an instruction to quote (61.4). The compensation event time bar guide takes each step in turn.
Quotations in three weeks
The Contractor submits a quotation within three weeks of being instructed to (62.3). It sets out the proposed changes to the Prices and any delay to the Completion Date and Key Dates, with the details of the assessment. Where the event alters the programme for the remaining work, the quotation includes the alterations to the Accepted Programme (62.2). The Project Manager replies within two weeks (62.3). If it does not, a failure notice and two more weeks of silence mean the quotation is accepted (62.6). How the money in a quotation is built is in the compensation event quotation guide.
Assessment at the dividing date
Each assessment divides at the dividing date. For an event that arises from a Project Manager's or Supervisor's instruction, notification, certificate or changed decision, it is the date of that communication. For any other event it is the date the event was notified (63.1). The change to the Prices covers the actual Defined Cost of the work done by that date, the forecast Defined Cost of the work not yet done and the resulting Fee.
Delay to the Completion Date is the time by which the event makes planned Completion later than planned Completion on the Accepted Programme current at the dividing date (63.5). Since the January 2019 amendments, the assessment takes into account any delay from the event that the Accepted Programme already shows. It allows too for events that happened between the programme's date and the dividing date. A contract still on the June 2017 wording does not carry that sentence. The dividing date guide works through it.
The Project Manager's assessment and implementing
The Project Manager assesses an event itself in four cases, all listed in clause 64.1. The quotation is late. The Project Manager judges it wrong and does not ask for a revised one. The Contractor has not submitted a programme or alterations the contract requires. The Project Manager has not accepted the latest programme for a reason the contract allows. When it does assess, it uses its own assessment of the programme for the remaining work if there is no Accepted Programme or a required programme or alteration is missing (64.2). When the Project Manager makes its own assessment covers clause 64.
Before deciding on a change, the Project Manager can also ask for a quotation for a proposed instruction (65). Silence works the other way here. If the Project Manager has not replied by the date it set for giving the instruction, the quotation is not accepted.
An event is implemented in one of three ways: the Project Manager accepts a quotation, notifies its own assessment or is treated as having accepted a quotation (66.1). Once implemented, an assessment is not revised except as the contract allows (66.3). A forecast that later proves wrong usually stands, though either party can still take the assessment to the dispute resolution option.
NEC Planning Solutions runs the monthly programme cycle for contractors on the NEC4 ECC, from each clause 32 revision to the early warning register and the compensation event clock, as part of its live project controls and reporting service. Monthly support starts from £1,400 plus VAT.
One event through the contract: a worked example
Take an illustrative job with the Completion Date at week 42. The Accepted Programme, accepted in week 8, shows planned Completion at week 40, so the Contractor holds two weeks of terminal float. It shows access to one work area at week 10, the same as that area's access date in the Contract Data. The six weeks of work in the area sit on a path with one week of float before planned Completion.
In week 6 the site team learns that the area may not be ready on time and gives an early warning. The early warning meeting looks at resequencing, but nothing else can move into the gap. In week 10 access is not given, so the event has happened: the Client has not allowed access by the later of the access date and the date for access on the Accepted Programme (60.1(2)). The Contractor notifies the compensation event that week. The event did not come from an instruction, notification, certificate or changed decision of the Project Manager or the Supervisor. So the eight-week bar applies to it in full (61.3).
The Project Manager replies in week 11, accepting it as a compensation event and instructing a quotation. Access is finally given at the start of week 13, three weeks late. The dividing date is week 10, the date of the notification (63.1). So the delay is measured on the programme accepted in week 8, the one current at that date (63.5).
In week 14 the Contractor submits its quotation. Its fragnet, the small set of activities added to the programme to model the event, shows the area's work starting three weeks late. One week of that is absorbed by the float on the path, so planned Completion moves two weeks, from week 40 to week 42. The quotation asks for the Completion Date to move by the same two weeks, from week 42 to week 44. It carries the change to the Prices and the altered programme (62.2). The two weeks of terminal float are untouched.
The Project Manager has two weeks to reply. If it accepts the quotation in week 16, the event is implemented (66.1). The Completion Date becomes week 44 and the next revised programme shows it. Had the Contractor waited until week 19 to notify, more than eight weeks after it became aware the event had happened, the Prices and the Completion Date would not have changed at all (61.3).
PLANNER'S TAKEAWAY The answer came from the programme accepted in week 8, the one current at the dividing date. It showed the float on the path, so the delay to Completion could be measured, not argued. With no Accepted Programme, any assessment the Project Manager made would have rested on its own view of the programme for the remaining work (64.2). |
How disputes are resolved: W1, W2 and W3
Every ECC carries one dispute resolution option. In England, Wales and Scotland the Construction Act covers most construction contracts. Northern Ireland has its own equivalent. Contracts the Act covers use W2. Either party can refer a dispute to adjudication at any time. The Senior Representatives stage is used only if both agree.
The Act does not reach everything. It leaves out some process plant work and contracts with a residential occupier. W1 is for contracts outside the Act: the Senior Representatives meet first, then adjudication follows. W3 adds a Dispute Avoidance Board that recommends before anyone goes to a tribunal. It is not for UK contracts the Act covers.
Whatever the route, a dispute about time turns on the programme record: the Accepted Programmes, their revisions and the trail of early warnings and compensation events. How a planner turns that record into evidence is in programme evidence in NEC claims and adjudication. The analysis methods are in NEC delay analysis and extension of time.
What changed from NEC3 and what comes next
NEC4 renamed several terms. The Employer became the Client, the Works Information became the Scope and the Risk Register became the Early Warning Register. It added proposed instructions, the Contractor's proposals to reduce cost, deemed acceptance of programmes and the Dispute Avoidance Board, among other changes. The clause-by-clause map is in NEC3 vs NEC4.
No NEC5 had been announced when this page was written in October 2026. NEC still sells the June 2017 edition, revised in January 2023. Where the administrative model is heading is discussed in the future of NEC contracts.
What to check in the Contract Data before you price
Most of the dates and periods that decide a compensation event are set before the job starts. These are the ones to read in the Contract Data before the tender programme is fixed. Read any Z clause that touches them too.
Whether a programme is identified in the Contract Data. If not, the period for the first programme, counted from the Contract Date.
The access dates for each part of the Site, against the sequence the tender programme assumes.
The Completion Date, any Key Dates and any sections under X5, against the time the work needs with time risk allowances included.
The period for reply and any longer periods set for particular replies.
The intervals for revised programmes and for early warning meetings.
The delay damages rates under X7, for the whole of the works and for each section.
Every Z clause, starting with any that change clauses 31, 32, 61 or 63.
The Client fixes most of them before tender. The tender programme has to live with each one. A programme identified in Contract Data part two is the Contractor's own and goes in with its price.
The author's view
About 60% of the projects I have planned ran on NEC, 20% on JCT and 20% on FIDIC. In my view NEC is the best of the three for the contractor's programme, because it is the most prescriptive about it.
I've planned jobs under NEC Options A, B and C. Each one asked something different of the programme. Option A was the most straightforward. The activities were the payment. Option B was harder. Quantities are hard to show on a programme built from activities. Option C was the most admin. The target kept moving with every compensation event.
That is why this guide reads the contract from the programme side. The clauses that decide time and money point back to one document. A contractor who keeps it accepted and current starts each compensation event in a stronger position.
Download the NEC4 programme clock
The main programme and compensation event periods on one page, each with its clause. Direct download, no sign-up.
NEC4 contract: frequently asked questions
What does NEC4 stand for?
NEC began as the New Engineering Contract. The family is now known simply as NEC. The 4 marks the fourth edition, launched in June 2017 to replace NEC3. When people say NEC4 they usually mean the Engineering and Construction Contract, though the edition covers the whole family, from the Professional Service Contract to the Term Service Contract.
What is the difference between NEC4 and the NEC4 ECC?
NEC4 is the whole edition, a family of contracts for construction, professional services, term services, supply, alliances and frameworks. The ECC, the Engineering and Construction Contract, is the member used between a Client and a contractor for construction or engineering work. It is the one main contractors sign, which is why "the NEC4 contract" in everyday use means the ECC.
Is NEC4 mandatory for UK public sector projects?
No. The Construction Playbook asks central government departments and their arm's length bodies to use standard contracts with suitable options unless a project justifies a bespoke approach, on a comply or explain basis. It names NEC alongside JCT and the PPC, TAC-1 and FAC-1 forms. NEC is widely used for UK public infrastructure, but the choice of form stays with the client.
What replaced the Works Information in NEC4?
The Scope. NEC4 renamed NEC3's Works Information as the Scope, the Employer as the Client and the Risk Register as the Early Warning Register. The Scope still states what the Contractor has to do and any constraints on how. A programme that does not comply with it can be refused acceptance. An instruction changing it is usually a compensation event (60.1(1)).
How long does the Project Manager have to accept an NEC4 programme?
Two weeks from submission, under clause 31.3. In that time the Project Manager accepts the programme or gives its reasons, which the contract limits to four. If it does neither, the Contractor can notify the failure. A further week of silence then counts as acceptance. NEC3 had no deemed acceptance of programmes, so this step is new in NEC4.
About the author
Roman Bazelchuk is the Founder of NEC Planning Solutions Ltd, a UK project planning and controls consultancy supporting contractors with NEC programme compliance, compensation event assessments and live project controls. He is an NEC Accredited Project Manager and holds the APMG Project Planning and Control qualification, with a BEng in Mechanical Engineering and postgraduate training in Planning and Control.
NEC Planning Solutions provides contract-aware planning support through a QA-governed delivery model, helping project teams keep programmes accepted, current and commercially useful from tender through to live delivery.
Is your programme set up for the contract you signed?
NEC Planning Solutions sets up and runs NEC4 programmes so that each revision, early warning and compensation event traces back to the Accepted Programme, as part of its live project controls and reporting service.
