How to write a monthly invoice statement email

Choose a cut-off and check the underlying invoices

Use a specific statement date and describe the summary as a snapshot. Before compiling it, check payments, agreed adjustments and invoice status using your normal records. A statement prepared last week may no longer describe what is outstanding today.

Group only invoices for the same customer and currency. Do not combine invoices belonging to similarly named businesses or add different currencies into one unexplained total. Check which accounts recipient handles this customer before sending the summary.

Keep the original invoice references visible. The statement helps the recipient find existing documents; it should not look like a fresh invoice for the total. Explain that each line refers to an invoice already issued and offer copies where needed.

Show what remains on each invoice

Each line should identify the invoice number, issue date, agreed due date, original amount and remaining balance. If you show a recorded payment, identify its date or reference clearly enough to explain the difference. Use the same currency throughout the section.

• Separate overdue balances from invoices not yet due.
• Explain any balance whose status is under review.
• Exclude cancelled items from an ordinary payment request.
• Check that payments have not been matched to two invoices.
• Label the total as the remaining balance at the statement date.

If you cannot match a transfer confidently, resolve it before presenting a precise balance as settled fact. An accurate line-by-line explanation is more useful than a tidy total assembled from unverified amounts.

Fictional example: £800 outstanding, £600 overdue

Ellis checks these three fictional invoices for one customer at 30 November 2026. The £150 received on 24 November has been matched to INV-802 in the business’s records. All amounts below are GBP.

The remaining total is £800: £300 + £300 + £200. The overdue subtotal is £600. Keep both labels in the cover email; neither the original £950 billed nor the £800 remaining should be presented as the overdue amount. Keep invoice issue dates in your full statement record alongside the due dates shown here.

Write a cover message with one clear request

State the customer name, statement date and purpose in the opening line. Then identify the overdue invoices you are asking about. “Please confirm the expected payment dates for INV-801 and INV-802” is easier to answer than a general request to review the account.

Invite the recipient to flag a missing invoice copy or allocation difference. If they believe a payment is missing, ask for the relevant invoice references and remittance details through your usual business route. Check the answer against received funds before updating the balance.

Subject: Invoice statement at 30 November 2026

Our checked records show £800 remaining across the three invoices listed: £600 overdue on INV-801 and INV-802, plus £200 not yet due on INV-803.

The £150 payment received on 24 November is allocated to INV-802. Please confirm expected payment dates for the two overdue invoices, or flag any allocation difference.

This summarises existing invoices; it is not an additional £800 invoice.

Coordinate the statement with invoice reminders

Check whether individual reminders are also scheduled. Decide whether the statement replaces a planned contact or simply provides context. Sending several reminders and a statement together can leave the recipient unsure which request to answer.

Record when the statement was sent, which invoices it included and your next review date. Update paid or queried invoices individually when new information arrives. A monthly summary complements the invoice records; it does not remove the need to keep each invoice’s status accurate.