Yellow Book Payment Toolkit (UK) — Cl.41 Payment Cycle, Pay Less, Suspension, Interest

Cl.41 of the Yellow Book operates the payment regime — Construction Act-aligned, strictly procedural, and full of deadlines that catch out Subcontractors who treat payment administration as an afterthought. Every cycle follows the same sequence: Application for Payment under cl.41.3 → Payment Notice within 14 days under cl.41.4 → Pay Less Notice not later than 1 day before Final Date for Payment under cl.41.7 → Final Date for Payment 35 days from Application (77 days for the final) under cl.41.5 → Interest under cl.41.8 if late. The deadlines are unforgiving but the protections are real. If the Contract Manager misses the 14-day Payment Notice deadline, cl.41.6 makes the Subcontractor's Application the sum due. If the Contractor misses the Pay Less Notice deadline (which is one day before Final Date for Payment, not the day of FDP), cl.41.7 requires the full notified amount to be paid. If the Contractor fails to pay by Final Date for Payment, cl.41.9 entitles the Subcontractor to issue a Notice of intention to suspend with a 7-day countdown, and after 60 days of continued suspension cl.41.10 escalates to termination. Late payment attracts compound daily interest at the Agreed Rate plus a margin that escalates from +2% in month one to +10% from month four onward under cl.41.8. The interest calculation is the part that catches Subcontractors out — not because it's hard, but because the rules are very specific. Cl.41.8 says daily compound interest. The margin starts at +2% in the first month of delay and increases by +2% per month up to a maximum of +10% from the end of month three. The principal compounds across each period. Done by hand on a calculator, an Application short by £5,000 over six weeks generates somewhere between £35 and £150 depending on how you read the clause. Done correctly, with daily compounding and the correct margin escalation, the answer is unambiguous. This toolkit administers the full cycle. The Application for Payment template calculates Subcontract Works value (percentage complete × Subcontract Price) plus implemented Variations plus agreed Claims plus other entitlements, less retention and previously certified amounts. Key dates — Payment Notice due, Final Date for Payment, Pay Less Notice deadline — calculate automatically from the Application date and type (interim or final). The Payment Register tracks every cycle with conditional formatting flagging PAID (green), UNDERPAID (red), AWAITING NOTICE (amber, if past the 14-day window), UNPAID — OVERDUE (red, if past FDP), AWAITING PAYMENT (blue, if PN issued and within FDP window) or CURRENT CYCLE. The Pay Less & Suspension tab includes a validity check on received Pay Less Notices (was it issued at or before FDP-1?) and a cl.41.9-compliant Suspension Notice template with the 7-day countdown automated. The Interest Calculator handles the cl.41.8 margin escalation with daily compounding across all four bands.