The final account is the whole job, agreed once

The final account is the last piece of commercial work on a JBCC contract. It takes the original contract sum and adjusts it for everything that actually happened, and the two parties agree the result. Done well it is a formality, because the work was kept current all along. Done badly it is an archaeology dig.

What goes into it

The final account is a structured adjustment of the contract sum, not a fresh valuation.

• The contract sum. The starting figure the parties agreed.
• Variations. Every instructed and valued change, added or omitted.
• Remeasures. Provisional quantities and provisional sums replaced with the measured actuals.
• Adjustments. Any contractual entitlements agreed along the way.
• Retention. Released in full once the defects period is closed.

It is a reconciliation, not a reconstruction

The single biggest determinant of how a final account goes is whether the variations were valued and certified as the job ran. A contractor that agreed each change in its own cycle arrives at the end with a settled account and a short list of open items. A contractor that let variations pile up unvalued arrives with a claim it has to rebuild from memory, against a principal agent who has every reason to doubt it.

Records decide the disputed items

By the final account, the easy items are long agreed and what remains is the contested handful. Those are won or lost on records, the instructions, the marked up drawings, the daily allocation sheets. There is no adjudication statute to fall back on for private work, so what settles the argument is either agreement or the contractual dispute route, and both reward the party with the better paper.

Then the retention comes home

Closing the final account is also when the last retention is released, once the defects period has run and the making good is done. That final tranche is the smallest and the most forgotten, so tie it to the account closure explicitly rather than leaving it to be noticed later.

The habit

Do not treat the final account as an end of job task. Build it from the first certificate by keeping the variation account current, remeasuring provisional items as the real quantities land, and reconciling retention each cycle. The final account is not written at the end. It is assembled all the way through and agreed at the end.