What is invoice matching (lettrage) in French accounting?

In practice, in France

Invoice matching is not a legal requirement in itself, but it is what makes the aged balance usable — and with it, customer collection, the year-end justification of third-party accounts, and the assessment of doubtful receivables. A poorly matched customer account leaves the notes to the accounts indefensible.

It is easy to conflate with bank reconciliation, but the two operate on different accounts and answer different questions. Bank reconciliation confronts the accounting bank account with the statement issued by the bank; invoice matching confronts an invoice with its settlement inside a customer or supplier account. A business can have a perfectly reconciled bank account and a completely unmatched customer ledger at the same time.

In Odoo

Odoo matches automatically when the amount and reference agree, and leaves the rest pending. The real work is on what is left: partial payments, grouped settlements, exchange differences, early-payment discounts. It is the unmatched volume, not the matched volume, that measures the health of the process.

Common mistakes

• Force-matching to “clean up” an account: the discrepancy disappears from the screen, not from reality.
• Only matching at closing, once no one remembers the underlying documents.
• Ignoring payment discrepancies instead of posting them as a loss or a discount.