Deposit, progress, final: invoicing a project step by step

Why invoice in three stages

A €20,000 project invoiced only at the end means €20,000 of cash-flow advance: materials paid to the merchant, wages paid, and you waiting. Staged invoicing spreads the effort — and it's a well-established practice.

1. The deposit invoice (at signature)

Issued as soon as the quote is accepted, usually 20 to 30% of the total. Two rules often forgotten:

• it's a real invoice, with a number in your sequence, legal mentions and VAT due on the amount received (for services);
• it must reference the signed quote.

The deposit secures your supplies and commits the client — a project with a paid deposit almost never gets cancelled.

2. Progress invoices (during the works)

On multi-week projects, invoice by progress: "Progress invoice #2 — 60% complete", billing the portion completed since the previous one. In practice: 60% of the contract, minus what has already been invoiced (deposit + previous progress invoices).

It's the ultimate anti-cash-gap tool: the project funds the project.

3. The final invoice (at handover)

At handover, the final invoice recaps the contract, lists everything already invoiced (deposit, progress invoices) and shows the remaining balance. It also carries, where relevant, the retention (typically released after the warranty period) and any additional works approved in writing.

The three classic traps

1. A deposit without an invoice — money received without a deposit invoice is an accounting and VAT irregularity.
2. Broken numbering — deposits and progress invoices belong to the same continuous sequence as all your other invoices.
3. A final invoice that recaps nothing — without a clear restatement of deposits and progress invoices, the client doesn't understand the amount, disputes it, and pays late.

Aidifis chains all three natively: signed quote → one-click deposit → progress invoices → a final invoice that deducts everything automatically, with the right VAT at every step.