The short answer
- One line per deliverable or per day, never both mixed. Pick the unit the client recognizes from the scope note.
- Name the thing, not the effort: 'Homepage redesign - second revision' not 'various design work'.
- Reference the agreement: a scope-note number or date in the reference column ends most 'what is this for' emails.
- Dates on every line. An approver who can't place the work in time can't approve it quickly.
- The one line that prevents disputes: 'Includes: the two rounds of revision agreed in the scope note. Additional rounds billed at [rate].' Written once, on every invoice.
The line, word for word
- Start with the noun the client uses: their name for the project, not yours. 'Acme site - homepage redesign' beats 'design services'.
- Add the stage: first draft, revision, final. Stages show progress and make partial invoices self-explanatory.
- Add the quantity in the client's unit: days, pages, pieces, hours - whatever the scope note priced. Mismatched units are the classic query trigger.
- The rate goes on the line, not just the total. Approvers with budgets approve faster when the math is visible.
- Group by project when a month has several, with one subtotal per project. Six flat lines across three projects reads like a mystery; three grouped sections read like a report.
Words that trigger queries
- 'Miscellaneous' - a query, every time. If it's real work, it has a name.
- 'As discussed' - discussable, therefore discussed. Put what was discussed in the line instead.
- 'Admin' - replace with the actual activity: 'project coordination and file management, Oct 1-15'.
- Round-day padding - invoice the honest 0.5. Approvers notice suspicious roundness, and trust is the currency that clears invoices fast.
The free tool for this
Invoice total, with a discount and a tax rate - Invoice total, with a discount and a tax rate. It runs in the page, asks for your own numbers, and sends nothing anywhere.
If you would rather not build it yourself
Client OS builds invoices this way by default: /invoice turns the day's work log into named, dated, scope-referenced lines with the revision policy attached - then remembers the invoice number, so /chase knows exactly what it's chasing. ClientOS is $19. See it on the shop, and there is a plain page about it here: what it holds.
Questions people actually ask
Should I include the hours if I billed a flat fee?
No - flat fee means the deliverable is the line, and hours invite re-derivation of your price. Show the deliverable, the stage and the fee; the math visibility rule is for time-based billing.
How much detail is too much?
The approver should understand every line in five seconds without asking you anything. If a line needs a follow-up email to explain, it was two lines pretending to be one.
Read next
How to keep track of unpaid invoices without a system you hate, What to look for in a client tracker before you pay for one, How to write a late payment reminder that actually gets paid, The client onboarding checklist that prevents every later argument, The one-page weekly review for a one-person business.