NEC Fee and Defined Cost Calculator
By Sheldon Wright MCICES. Last reviewed September 2026. For the NEC3 and NEC4 ECC.
The most argued-over line in a compensation event quotation is the Fee, and most of the argument is about which percentage applies to what. Choose your contract, enter the Defined Cost by component, and this works out the Fee the way the contract does — including the part people get wrong, which is that under NEC3 every pound carries one fee percentage, never two.
Nothing you type here is sent to us. The calculation runs in your browser.
The change to the Prices
Which fee percentage applies to what
NEC3 has two, and nothing takes both. Clause 11.2(8) makes the Fee the subcontracted fee percentage on the Defined Cost of subcontracted work plus the direct fee percentage on the Defined Cost of other work. The usual mistake is to charge the subcontracted percentage on the subcontracted lines and then the direct percentage on a total that still contains them, which overstates the quotation by the direct fee on every subcontracted pound.
NEC4 has one. The fee percentage applies to all of Defined Cost, and the overhead percentages NEC3 carries were folded into it. A quotation that shows both an NEC4 Fee and a Working Areas overhead is describing a contract that does not exist.
Where subcontracted work sits depends on the schedule. Under NEC3 Options C, D and E, payments to Subcontractors are not a component at all — they are Defined Cost in their own right, alongside the components. Under Options A and B the subcontracted work is built up from the same components as if the Contractor were doing it, so it is a portion of what is already counted, not an addition to it.
The Fee goes on top of the risk allowance. And a risk allowance carried against subcontracted work is Defined Cost for subcontracted work, so under NEC3 it takes the subcontracted percentage.
Frequently asked questions
Which fee percentage applies to subcontracted work under NEC3?
The subcontracted fee percentage, and only that one. NEC3 clause 11.2(8) makes the Fee the subcontracted fee percentage on the Defined Cost of subcontracted work plus the direct fee percentage on the Defined Cost of other work, so nothing carries both.
Does NEC4 still have two fee percentages?
No. NEC4 applies a single fee percentage to all of Defined Cost, and the overhead percentages NEC3 carries were folded into it. A quotation showing an NEC4 Fee and a Working Areas overhead is describing a contract that does not exist.
Is the Fee charged on the risk allowance?
Yes. The Fee is applied to the Defined Cost including the risk allowances assessed under clause 63. Where the risk relates to subcontracted work it is Defined Cost for subcontracted work, so under NEC3 it takes the subcontracted fee percentage.
Are payments to Subcontractors part of Defined Cost?
Yes, but where they sit differs. Under NEC4 they are component 4, inside the Schedule. Under NEC3 Options C, D and E they are not a component at all, and are Defined Cost in their own right. Under NEC3 Options A and B subcontracted work is built up from the same components as if the Contractor did it.
Does the calculator send my figures anywhere?
No. The calculation runs in your browser and no amount you type is sent to us.
The Fee is the easy part.
Clause 60 reads the notification, the quotation, the programme and the records against your contract including its Z clauses, and returns a structured review in about ten minutes. Every finding is cited to its source document and labelled Fact or Inference. It is assistive: you make the call.
This calculator gives indicative figures on the standard NEC3 and NEC4 forms. It is not legal or contractual advice, and it does not account for the amendments in your contract. NEC is a registered trade mark of its owner; Clause 60 Limited is not affiliated with or endorsed by NEC.