Consulting engagements often combine a flat fee for the core scope with hourly billing for anything that runs beyond it, plus reimbursed expenses like mileage. Keeping those three kinds of charges on separate lines makes the invoice match the proposal the client already signed off on.
Consulting invoice example
Here is a filled-in example for a strategy engagement with extra interviews and mileage. Adjust the fee structure and rates to match your own contract.
renata@example.com
Chicago, IL
Attn: Owen Blake
1500 Industrial Pkwy
Chicago, IL 60632
TermsNet 14
| Description | Qty | Rate | Amount |
|---|---|---|---|
| Strategy engagement, phase 1: operations audit (flat fee) | 1 | $4,500.00 | $4,500.00 |
| Additional stakeholder interviews (hours) | 5 | $200.00 | $1,000.00 |
| Mileage (round trips to client site) | 120 | $0.65 | $78.00 |
What to include on a consulting invoice
- Your business name and contact details. Your name or firm name, email address and location.
- The client's billing details. Company name, contact person and billing address.
- A unique invoice number. Useful once you are running several engagements at once.
- The engagement or phase name, matching your proposal or statement of work.
- Flat fees, hourly extras and expenses as separate lines. Do not combine them into one total.
- Retainers already applied, subtracted so the balance due is what is actually owed.
How to word your line items
Naming the phase and the specific extra work, rather than a single "consulting services" line, is what lets a client's accounts payable department approve the invoice without a follow-up call.
- Flat engagement fees: "Strategy engagement, phase 1: operations audit (flat fee)" names the scope directly.
- Hourly extras: work beyond the agreed scope, such as extra interviews, billed with the hours and rate shown. See the hourly invoice template for this layout.
- Expenses: mileage or travel listed with the quantity and rate, so the client can see it is a reimbursement, not a markup on your fee.
Payment terms for consulting work
- A retainer against future work, applied as a credit on invoices as the engagement progresses.
- Net 14 or Net 30 for established clients and ongoing engagements.
- Milestone billing tied to project phases, for larger consulting engagements.
Invoice payment terms explained covers how to structure terms for project-based work.
Making the invoice with the Invoice Generator
- Open the Invoice Generator and start the invoice for the current engagement or billing period.
- Add the flat fee, hourly extras and expenses as separate lines.
- Create a free account to save it. Your work is kept while you sign up, and your logo appears on every invoice you send.
- Share the invoice link or download the PDF. You can see when the client has viewed it, and they can comment directly on the invoice with questions.
If you track your hours in the app, unbilled time converts into invoice lines in one step, so hourly extras do not need to be re-entered by hand.
