Final Account

A final account is the process by which a contractor and a client agree the total amount due at the end of a construction contract. It starts with the original contract sum and works through every financial adjustment made during the project - agreed variations, changes to provisional sums, fluctuations, loss and expense claims, and any contra charges - to arrive at a definitive figure. Once agreed, the contract administrator issues the final certificate, which triggers the last payment and formally closes out the financial obligations of the contract.

Final accounts are typically prepared at the end of the defects liability period, once all notified defects have been rectified. Under most standard forms - including JCT and NEC contracts - the contractor is required to submit all documents necessary for the adjustment of the contract sum within a specified timeframe after practical completion. Leaving this too late weakens the contractor's position and can result in the contract administrator issuing a final certificate based only on the information available to them.

What Goes Into a Final Account

The final account reconciles every financial element that moved during the project. The starting point is the contract sum as tendered. From there, the following adjustments are applied:

• Agreed variations: additional works instructed by the client and valued against the contract rates or agreed daywork rates
• Provisional sums: replaced with the actual cost of the work that was executed
• Prime cost sums: updated to reflect actual nominated sub-contractor and supplier costs
• Fluctuations: applied where the contract includes provisions for input cost changes
• Loss and expense: additional costs claimed by the contractor for employer-caused delays or disruptions
• Liquidated damages: deducted if the contractor overran the contract completion date
• Retention release: the second half of retention held back since practical completion

Common Causes of Final Account Disputes

Final account disagreements most often arise from three sources. First, poorly evidenced variations - instructions that were verbal or informal and where the client disputes that the work was ever authorized. Second, unresolved provisional sum expenditure where the actual cost differs significantly from the budgeted figure and the client contests the difference. Third, loss and expense claims where the contractor has not maintained contemporaneous records needed to demonstrate cause and effect.

The final certificate issued after agreement is conclusive on all matters it covers. Disputes must typically be raised within 28 days under JCT contracts - after which the certificate becomes binding. Under NEC contracts, the equivalent is the final assessment, which follows a structured programme of assessments leading to final account agreement.

How Zigaflow Supports Final Account Preparation

Contractors who manage their jobs in Zigaflow maintain a single record of every variation raised, every purchase order placed, and every sub-contractor cost captured. When the time comes to prepare a final account, that job record provides the audit trail - valued variations against budget, actual procurement costs, and a clear timeline of instructions and responses. That is significantly faster than reconstructing the picture from scattered emails, spreadsheets, and site diaries.