FeewrightWhat to put on a consulting invoice (with a field-by-field template)
A clear invoice gets paid faster and questioned less. Here is every field it needs, and how to lay out mixed hourly, retainer and pass-through work.
The fields every invoice needs
| Field | Why it matters |
|---|---|
| Your business name and contact details | Accounts-payable teams match invoices to vendors by name. |
| Client name, billing contact and address | Routes the invoice to the person who approves it. |
| Invoice number | Unique and sequential (e.g. 038, 039). Clients reference it when they pay. |
| Issue date and due date | Spell out the due date rather than only “Net 15”. |
| Service period | “October 1–31” avoids “which month is this for?” emails. |
| Line items | Date, description, hours or quantity, rate, amount. |
| Total due | And any amount already paid, if the invoice is partly settled. |
| Payment instructions | On every invoice — ACH details, check address, or a payment link. |
| PO or reference number | If the client uses purchase orders, invoices without them often stall. |
Laying out mixed work
Many consultants bill a mix on one invoice. Put the predictable items first and the variable ones after:
- Retainer: “Advisory retainer — up to 20 hours (October)” as a single line.
- Pass-through costs: name the vendor — “Data platform usage (Snowflake), October”. Named vendors look like what they are; vague lines look like padding.
- Hourly work: one line per entry with the date and a short, client-facing description: “Oct 14 — Requirements call with finance team (1.5 h)”.
- Overage: “Additional hours beyond retainer (4 h at $200)”.
Writing line-item descriptions
- Describe the outcome, not the activity: “Fixed refresh failure on revenue dashboard” beats “Troubleshooting”.
- Name people and deliverables the client will recognise.
- Keep it to one line. If a client wants detail, they will ask — and you will have it in your log.
Payment terms that get paid
- Net 15 is normal for independent consultants; Net 30 is common with larger companies.
- Invoice on a fixed day — the 1st of the month is easiest to remember on both sides.
- Follow up on a schedule: a friendly note the day after the due date, a firmer one at 7 days, a call at 14.
Common mistakes
- Invoicing weeks after the month ends — late invoices get paid late.
- Missing payment instructions on the second and later invoices.
- Reusing or skipping invoice numbers.
- Rounding hours down from memory instead of billing what you logged.