Mandatory items on a construction invoice

Numbering

Continuous, chronological, unbroken. It's the first thing auditors look at: two invoices with the same number, or a skipped number with no explanation, and the accounts are deemed unreliable.

Terms and penalties

Due date, late-payment interest rate, and the flat recovery fee between businesses. These are mandatory even if you never intend to apply them.

Warranties

For construction work: one-year completion, two-year, ten-year. They reassure as much as they commit.

Deposit already paid

If a deposit was taken, the balance invoice must state and deduct it explicitly. Otherwise the client pays twice — or believes they did.