What is a JCT contract?
A standard form of building contract published by the Joint Contracts Tribunal, chosen by the employer to suit the procurement route, with set rules for payment, changes, completion and the final account.
Updated: 15 September 2026. By Jack Butler-Kettle, Quantity Surveyor & Claims Consultant.
The answer
A JCT contract is any of the standard forms published by the Joint Contracts Tribunal, the body that has produced building contracts for the UK industry since 1931. The family covers the procurement routes in common use: the Standard Building Contract for traditional work with a full design, the Design and Build Contract where the contractor designs, the Intermediate and Minor Works forms for smaller or simpler jobs, and matching subcontracts and consultant appointments, all in a 2016 edition with a 2024 edition being adopted. What they share is a fixed set of machinery: interim payments on a set timetable with Payment Notices and Pay Less Notices, a variation procedure with valuation rules, extensions of time for listed Relevant Events, loss and expense for listed Relevant Matters, practical completion, a rectification period and a final account. The contract you sign is rarely the standard text: schedules of amendments change the risk allocation, the payment periods and the notice rules, so the amended form governs and the printed form is only the starting point.
Example
The situation
A £4m office fit-out is let on the JCT Design and Build form with a 40-page schedule of amendments. The printed form sets a 14-day final date for payment; the amendments make it 28 days and require applications on a bespoke template.
What happens
- The schedule of amendments is read against the printed form to see what was changed: the 14-day final date becomes 28 days and applications must go on the bespoke template.
- The subcontractor's payment diary is built from the amended terms.
- The notice template and the variation register are built from the amended terms in the same way.
The outcome
Every working document runs to the 28-day final date and the bespoke application template; the printed form is used only to see what was changed.
Signed Contract Review reads the amended form you actually have and hands back the dates and clauses that bite.