You delivered the strategy, the report, or the advice — and it was good. Now you need an invoice that reflects the value of what you provided. Consulting invoices are straightforward in principle but easy to get wrong: vague descriptions, missing payment terms, and no record of agreed scope are the three most common reasons consultants wait longer than they should to get paid. Here's how to get it right.
What to Include on a Consulting Invoice
1. Your business information
Your name or company name, registered address, email, and phone. If you're VAT registered or incorporated, include your registration number. For senior consultants billing large organisations, this detail matters — accounts teams won't process an invoice without it.
2. Client information
The full legal name and address of the company or individual you're billing. For corporate clients, include the name of the internal sponsor or project lead, and any purchase order (PO) or cost centre reference they require. Missing a PO number is one of the most reliable ways to delay payment by 30 days.
3. A unique invoice number
Sequential, one per invoice. It's the reference for any payment query, expense reconciliation, or audit trail. Never skip it.
4. Invoice date and payment due date
Net 30 is standard for consulting work with corporate clients. Net 14 is reasonable for smaller businesses and individual clients. State the due date explicitly — don't rely on the client to calculate it from "net 30."
5. Itemised breakdown of work
This is where most consulting invoices fall short. "Consulting services — $4,500" tells the client nothing and invites questions. Break it down by deliverable or by time period:
Strategy workshop: Half-day facilitation session, 15 March (flat fee $1,800)
Research and analysis: Competitor landscape report (12 hrs @ $175/hr)
Advisory calls: 4 x 1-hour sessions, weekly check-ins (4 hrs @ $175/hr)
Written recommendations: Final report and executive summary (flat fee $1,200)
6. Expenses (if applicable)
Travel, accommodation, subsistence, and any third-party costs incurred for the engagement should be line items. Include receipts or a brief note. Most clients expect to reimburse expenses — they just need to see them itemised and within any pre-agreed limits.
7. Retainer billing (if applicable)
If you work on a monthly retainer, invoice it as a single line with a clear description of the period and what's included: "Monthly advisory retainer — April 2026 (20 hrs, weekly calls, ad-hoc support): $3,500." Add any hours used above the retainer threshold as a separate line.
8. Subtotal, taxes, and total
Tax as a separate line — especially important for cross-border invoicing where VAT, GST, or withholding tax rules vary. Total at the bottom, unambiguous.
9. Payment terms and methods
Bank transfer details are standard for consulting. For international clients, include your SWIFT/BIC and IBAN. Currency should be explicit — USD, GBP, EUR — especially if you work across borders.
Free Consulting Invoice Template
Copy and adapt for your next engagement:
[Your Name / Company Name]
[Registered Address] | [Email] | [Phone] | [VAT/Company Reg Number]
Invoice #: INV-001 Date: [Date] Due Date: [Date + 30 days]
Bill To:
[Client Company Name]
[Billing Address]
[Accounts Contact Name and Email] | PO #: [if applicable]
Description | Qty | Unit Price | Total |
|---|---|---|---|
[Deliverable – e.g. Strategy workshop] | 1 | $[amount] | $[amount] |
[Time-based work – e.g. Research] | [X hrs] | $[rate]/hr | $[amount] |
Expenses – [travel, accommodation, etc.] | $[amount] |
Subtotal: $[amount]
Tax ([X]%): $[amount]
Total Due: $[amount]
Payment methods: Bank transfer
Bank details: [Account name] | [Sort code / Routing number] | [Account number] | [IBAN / SWIFT if international]
Late payments are subject to a [X]% monthly fee after [30] days.
Common Mistakes Consultants Make on Invoices
Vague descriptions. "Consulting services" is not a description. Specify what you did, when, and how long it took. The more detail, the fewer questions.
No PO number. Corporate clients often can't process an invoice without one. Ask for it at the start of the engagement — not when the invoice bounces back.
Waiting until end of month. Invoice as soon as a deliverable is complete. Waiting until month-end unnecessarily delays your payment by weeks.
Not specifying currency. For any international work, make the currency explicit on the invoice. Ambiguity causes delays and, occasionally, underpayment.
The Faster Way to Invoice
Consulting work is already administratively intensive. Invoicing doesn't need to add to it. Clervo lets you build and send a professional invoice in under a minute, track payment status across multiple clients, and send automatic reminders when due dates approach.
You delivered the value. A clear invoice makes sure you're paid for it.