The invoice follows a certification, not a sale
Work is valued, submitted for certification, and only then invoiced. The timing and the amount are determined outside your accounting system, which affects when a compliant invoice can even be issued.
Contracting & construction
Contracting invoices are not raised freely — they follow a valuation that has been submitted, reviewed and certified, often weeks after the work. Retention is withheld, variations are argued, and payment applications and tax invoices are not the same document. Structured invoicing has to accommodate all of that without changing how the commercial process works.
Work is valued, submitted for certification, and only then invoiced. The timing and the amount are determined outside your accounting system, which affects when a compliant invoice can even be issued.
Amounts withheld across the life of a project and released long afterwards create documents that reference work invoiced months or years earlier.
Where a certified amount differs from the application, the resulting adjustment has to be represented as a proper structured document rather than an informal correction.
Valuations and cost tracking in a project system, invoices raised in the ledger, with the link between them maintained manually more often than not.
Payment applications and certificates frequently exist as spreadsheets or PDFs, with only the final figure entering the accounting system.
Project-specific entities and JV arrangements each carry their own tax position and scope question.
Where projects are run through separate entities, each needs its own scope and deadline answer.
How retention is shown on the invoice and how its later release is documented needs settling before go-live.
If the certified figure arrives by email and is keyed in manually, that step becomes part of the compliance chain and needs to be reliable.
Tax treatment of retention and certified amounts is a question for your tax advisor. We work alongside them rather than substituting for them.