How to write an invoice for accounting services

An invoice for accounting services names the client's legal entity and the period covered, shows each fixed fee, extra job and disbursement on its own line, and carries VAT where it applies. Tie each fixed fee to the engagement letter, so nobody has to ask what the amount was for.

What must an accountant's invoice include?

An accountant's invoice must first meet the ordinary invoice rules, then answer the questions accounting clients actually ask. In the EU, Article 226 of the VAT Directive sets the required details, and the guide to VAT invoice fields goes through them one by one. Here's what they mean for accounting work.

A worked example: one month's invoice

Here's an invented example. A bookkeeping practice invoices a small company in April for March's work, charging 20% VAT.

The total is €672.00 plus €134.40 plus €15.00. The client can see in ten seconds what's routine and what's extra, and the extra line says who agreed it. That line is the one most likely to be queried, so it has the most words.

How should you describe accounting work on an invoice?

Describe accounting work by naming the service, the period and the agreement it falls under. "Professional services: €2,400" is the line a client rings about.

This wording is enough for a year-end fee:

Preparation of statutory accounts and corporation tax return, year ended 31 December 2025. Fixed fee per engagement letter dated 12 January 2026.

Watch for descriptions that overlap. ICAEW's fee information helpsheet gives the example of a client who paid for "accounts preparation", later saw "finalising accounts" for the same period, and concluded they had been charged twice. If two invoices touch the same period, say what's different about the second.

ICAEW members must also provide a fee breakdown if a client asks for one, with enough detail for the client to understand how the fee was calculated. Clear lines make that request less likely, and easier to answer when it comes.

Which costs are disbursements on an accountant's invoice?

A cost is a disbursement for VAT purposes only when you paid it as your client's agent and recharge the exact amount, which is a narrower test than most practices assume. HMRC's VAT Notice 700, section 25 lists the conditions, and the EU basis is Article 79 of the VAT Directive.

• Likely to qualify: a filing fee the client owes, which you paid on their behalf with their authority, and recharged at cost.
• Unlikely to qualify: your own travel, postage and phone. HMRC says that test usually rules these out. They go through as part of your fee, with VAT on them.
• Check first: a software subscription you hold and recharge. If the supplier invoices you, that usually points to it being part of your own supply.

The guide to VAT on reimbursable expenses and disbursements covers the test in full. If you're unsure, ask before excluding a cost, because leaving one out of the VAT sum when it doesn't qualify is a VAT error on your invoice.

How do you invoice an accounting client in another country?

An accounting client in another EU country is usually invoiced without VAT under the reverse charge, provided the client is a business. Services to a business are generally supplied where the customer is established (Article 44), the customer accounts for the VAT (Article 196), and your invoice must say "Reverse charge" (Article 226(11a)).

Private clients are different. Accountants' services to a private individual living outside the EU are supplied where that person lives (Article 59(c)). The guides to invoicing EU clients and reverse-charge wording take this further.

The mistakes that get accounting invoices queried

• Addressing the director instead of the company. The company then holds an invoice in someone else's name.
• One invoice for a group. Each entity needs its own, or none of them can tie the cost to their own books.
• Payments on account with no invoice trail. ICAEW warns that standing orders can make clients assume the payments cover everything. Say what they cover, and be ready to reconcile fees against payments.
• Extras with no agreement cited. "Additional work: €400" invites a dispute. The date and the email settle it.
• A fixed fee with no period. "Monthly fee" could be any month. Name it.

What the fee covers belongs in the fees section of your engagement letter, and the invoice only has to point back to it.

Invoicing accounting clients in ERPFlow

ERPFlow runs the practice rather than your clients' books. The page on accounting and bookkeeping practices sets out where that line sits: no double-entry ledger, bank feed or statutory filing.

• Fees: set up each one as a service with its price. Pick it on the line, then type over the description to add the period and the letter's date.
• Invoices: an invoice takes a tax rate per line, prints in the client's language and is frozen on issue, including the client's details. The Order number field holds a client's purchase order, and Notes print on the PDF.
• Monthly fees: a recurring invoice bills them on schedule, with identical lines each run. Choose Create drafts if you want to add the month or an extra before issuing. It issues and never collects, so payments go in by hand.
• VAT: you set up your own tax rates, including a reverse-charge type, and choose one per line. ERPFlow doesn't pick a rate from the client's country or check VAT numbers in VIES, so read the PDF for the wording your tax authority wants, and add anything missing in Notes.

There's no credit note document. An issued invoice is corrected with Mark as void and Duplicate, which gives you a new draft to fix and issue under a new number.