JCT Subcontract Payment & Notice Deadline Calculator

Core Provisions in Standard JCT Subcontracts

When navigating interim valuations under standard JCT subcontracts, payment calculations follow this critical sequence:

• Interim Valuation Date (IVD): The established monthly baseline date agreed in the Subcontract Particulars from which subsequent dates and notice windows are triggered.
• Due Date: Calculated according to the selected JCT form, edition, and Subcontract Particulars. The interval is not identical across all JCT subcontracts.
• Relevant Payment Notice or Certificate: Depending on the JCT form and payment mechanism, the payer, contract administrator, or specified party must issue the relevant notice or certificate within the contractual period (typically no later than 5 calendar days after the Due Date), specifying the sum considered due and the basis of calculation.
• Pay Less Notice Deadline: If the payer intends to pay less than the notified sum (or the subcontractor’s payment application where applicable), a valid Pay Less Notice must be served no later than the prescribed period before the Final Date for Payment (typically 5 calendar days in standard unamended forms).
• Final Date for Payment: Calculated according to the selected JCT form, edition, and any bespoke amendments. Payment must be made by the contractual Final Date for Payment, subject to any valid notice served under the contract.

Subcontract Differences & Bespoke Amendments

Application mechanisms and notice rules differ depending on the form in use:

• DBSub vs SBCSub: Rules governing when and how a subcontractor’s interim payment application takes effect in default of a contractor notice depend on the specific edition and whether the application was served in strict accordance with the contract timetable.
• Bespoke Amendments: Main contractors frequently modify these default intervals in bespoke schedules. Amendments often extend the Final Date for Payment to 28, 35, or 60 days, or compress the contractor’s Pay Less Notice period down to 1 or 2 days prior to the Final Date for Payment.