Process Automation4 min read

Quote to Invoice to Paid: Claude Code for SME Invoicing

Turn accepted quotes into correct invoices, chase payments politely on schedule and see who owes what, with Claude Code recipes and one numbering file.

Haojun See

Founder & Director, On The Ground

Updated 3 November 2026

What the Get Paid track covers

Get Paid covers the work after a client says yes: issuing the invoice correctly, reminding people on time, and knowing who owes what. It's the least glamorous track and often the one that matters most to cash flow. Four recipes cover it: accepted quote to invoice, payment chasing, a monthly receivables report, and receipts to an expense ledger. Each one depends on a simple principle: a chat window can't hold a ledger. Numbers live in files, and the recipe reads and updates those files.

Recipe 1: Accepted quote to invoice

Ask Claude Code to copy the line items, milestone and amount straight from the accepted quote, take the next number from your numbering file, and fill your invoice template. Copying instead of retyping is the point: most invoice errors are typing errors. 1. Put the accepted quote, the client's billing contact and PO number, your template and numbering.csv in the folder. 2. Ask for the invoice with the next number, then update the numbering file. 3. Set the due date to your standard terms, such as 14 or 30 days. 4. Draft the cover email. Check the amount, number, bank details and PO before sending. If you're GST-registered, IRAS sets out what a tax invoice must show, including your GST registration number, on its invoicing customers page/basics-of-gst/invoicing-price-display-and-record-keeping/invoicing-customers). Put those fields in your template once and the recipe fills them every time.

Recipe 2: Payment chasing without the awkwardness

Keep a list of open invoices and ask each morning for today's actions: a heads-up three days before the due date, a "did this reach the right person?" one day late, a direct note with the invoice at 14 days, and a phone call at 30. The schedule takes the emotion out of chasing. Claude drafts each message in your voice and updates the list with what was sent. One check comes first, every time: look at this morning's payments, so you never chase someone who has already paid.

Recipe 3: The monthly receivables report

Match the month's bank export against open invoices, group what's owed by age, and ask for a one-page summary with three actions. The age bands are current, 1–30, 31–60 and over 60 days. Check any unmatched payments by hand. The report is short on purpose: who owes what, since when, and what you'll do about it this week.

Recipe 4: Receipts to an expense ledger

Point the recipe at a folder of receipts and ask it to extract the date, vendor, amount, currency and GST, assign your categories, remove duplicates and export a CSV for your accountant. Anything unclear goes to a separate review file rather than being guessed. We run this one on our own books. The review file is the important output: it's the short list of items a person needs to look at, instead of the whole pile.

Where to be careful

Money is where mistakes cost most, so every Get Paid recipe ends with a human check. • One numbering file. Never let two tools or two people issue numbers separately. • Bank details come from your template, never from a chat or an email thread. • Draft, don't send. Chasing emails are drafts you approve. • Use proper software when you outgrow files. If you issue many invoices a month, an accounting or invoicing app is the better ledger, and Claude Code can prepare the data for it.

Next steps

Start with quote-to-invoice, because it fixes the most common errors fastest, then add the morning chase. After a month, run your first receivables report. Come and talk it through in person. Our year-end OTG Christmas Gathering is on Monday 28 December in Singapore: an evening of networking, dinner and a gift exchange with the people we've worked, learnt and built with this year. Bring the one job you'd most like to hand over, and we'll show you how we'd set it up. Register on Luma.

This guide is part of our series on running a small business with Claude Code as the harness. • Get Seen, Get Sales, Get Paid with Claude Code: the main guide: the three tracks and how a recipe works. • Get seen by AI, not just Google: a month of content in your voice, and a check on how ChatGPT, Claude and Perplexity describe you. • From call notes to quote: pipeline tidy-ups, quotes from your own price list, and follow-ups that go out on time. • A weekly Claude Code routine for a one-person company: how the three tracks fit into one week when you are the whole team.

Frequently asked questions

Can AI create invoices for a small business?

Yes, if it copies from the accepted quote and your template rather than writing from scratch. Give it the quote, the client's billing details, the template and a numbering file, and ask for the next invoice number and a draft email. A person checks the amount, number, bank details and PO before it goes out.

What must a tax invoice show in Singapore?

IRAS lists the required details for a GST tax invoice, including your GST registration number, the invoice number and date, the customer's details, a description of the supply, and the GST amount. A tax invoice goes to GST-registered customers. Check the IRAS invoicing page and build the fields into your template.

How do I politely chase an overdue invoice?

Use a fixed schedule so it never feels personal: a friendly heads-up before the due date, a check that the invoice reached the right person one day late, a direct note with the invoice attached at about 14 days, and a phone call at 30. Always check for payment first.

Can Claude Code replace my accounting software?

No, and it shouldn't. Claude Code is good at preparing and checking data: drafting invoices from quotes, matching payments and sorting receipts. A proper accounting or invoicing app should hold the ledger once volumes grow. Use Claude Code to feed it clean data and to produce the reports you need.

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