thinkhard.SI

Prompt repository Finance & accounting

Write an invoice and payment terms from work done

You need a clear invoice description, line items and payment terms that reduce late payment.

Registry no.
FIN-011
Collection
Finance & accounting
Laid out for
Any chat model
Score
10 out of 10
Blanks to fill
8
Added

Finance & accountingAny chat

The prompt

Score 10 of 10, Excellent

Use it when You need a clear invoice description, line items and payment terms that reduce late payment.

  • {{my_business}}
  • {{customer}}
  • {{invoice_number}}
  • {{invoice_date}}
  • {{tax_info}}
  • {{payment_methods}}
  • {{agreed_terms}}
  • {{work_done}}
Full prompt and why it works
Prompt
My business: {{my_business}}
Customer: {{customer}}
Invoice number and date: {{invoice_number}}, {{invoice_date}}
Tax to show: {{tax_info}}
How the customer can pay: {{payment_methods}}

What was agreed (quote, contract or email: rates, payment terms, any late fee clause):
"""
{{agreed_terms}}
"""

Work done (what was delivered, dates, hours or quantities):
"""
{{work_done}}
"""

Task: Write an invoice for the work above, plus a short email to send it with. It goes to the customer's accounts payable team, who will approve it only if they can match it to what was ordered. The goal is an invoice they can approve on first reading, so clarity matters more than polish.

Requirements:
- Line items: a description that names the deliverable and dates in the words of the agreement (for example, "Website copy, 6 pages, delivered May 12, per quote Q-114" shows the form), then quantity, rate and amount. Show each line's calculation.
- Use only the rates in the agreement. If the work done goes beyond what was agreed, list it separately for me to decide on; do not bill it.
- Subtotal, tax and total with the sums written out. Calculate tax only with the rate I gave; if I wrote "none", show no tax line.
- Payment terms: the due date as an actual date, worked out from the invoice date and the agreed terms, plus how to pay and who to contact with questions. Include a late fee only if the agreement contains one, worded as it is there.
- Include the customer's purchase order number if they have one, because many accounts payable teams reject invoices without it.

Format:
1. The invoice laid out top to bottom as plain text, ready to copy into my invoicing tool or a document.
2. The cover email: a subject line with the invoice number, and up to 80 words.
3. Missing details: anything an invoice normally needs that I have not given, such as a PO number or the customer's billing address.

If anything is missing, write [ADD: what is needed] in the invoice instead of inventing it. Do not invent tax IDs, bank details or contract terms.

Invoice and tax requirements differ by country and state, so have an accountant confirm the tax lines and required details before you rely on this layout.

Variables

{{my_business}}
Your business name and address, and any tax registration number your accountant says to show.
{{customer}}
The customer's legal name, billing address, billing contact and purchase order number, if any.
{{invoice_number}}
Your next invoice number.
{{invoice_date}}
The date of the invoice.
{{tax_info}}
The tax rate to apply and its name, as your accountant set it, or "none".
{{payment_methods}}
How the customer can pay, for example bank transfer or a payment link. You can add account numbers yourself afterward.
{{agreed_terms}}
The quote, contract or email that set the rates and payment terms, including any late fee clause.
{{work_done}}
What you delivered, with dates and hours or quantities.

Why it works

  • Who it's for. Writing for the customer's accounts payable team, who must match the invoice to an order, is what puts the PO number, the agreed wording and an actual due date on the page.
  • What to avoid. Only agreed rates are billed, extra work goes to a separate list for you to decide on, and a late fee appears only if your agreement has one.
  • If unsure. Missing details are marked [ADD: ...] in the invoice and listed, instead of being filled with an invented tax ID or bank detail.

How to use it

  1. Press Fill in variables and type your details into each blank. What you type stays in this browser.
  2. Copy the filled prompt into the AI tool you already use, such as ChatGPT, Claude or Gemini, or open it in the Grader or the Prompt Tester here.
  3. Before you rely on it, try it on three or four real examples. The Prompt Tester runs them all at once and shows which ones go wrong.
Use it from code

Get this prompt as JSON from the free REST API, with your own text in the blanks, or let an AI assistant fetch it through the MCP server. No key.

curl -s https://thinkhard.si/api/v1/prompts/invoice-with-payment-terms

With the MCP server added to Claude, ChatGPT, Cursor or VS Code, call get_prompt with {"prompt": "invoice-with-payment-terms"}, or just ask for it by name.