Who hasn't paid? FreeAgent invoices in ChatGPT and Claude

How to connect FreeAgent to ChatGPT or Claude

A client tells you “we paid last week”, but FreeAgent still lists their invoice as overdue. Often the money is already in the bank, sitting unexplained, and with the VAT payment due on 7 November you want to know which it is. Once FreeAgent is linked, ChatGPT or Claude can check while you’re still on the phone. We checked on 23 October 2026: FreeAgent had no official connector in the ChatGPT or Claude catalogs.

1. Get APIUniCon into ChatGPT or Claude with the setup guide, unless it’s already there from another service.
2. Ask for the connection in the chat: “Connect my FreeAgent”. The FreeAgent API docs are the link to give if the AI wants to read up first.
3. Allow access in FreeAgent. There is no key to create here. FreeAgent’s OAuth page explains that users authorise apps without sharing their FreeAgent login: you sign in on FreeAgent and get a screen where you allow or deny access. The link the AI sends opens our page, and our page takes you to that screen. Sign in and allow.
4. Wait a few seconds for the test request. The AI will say what it can read: invoices, contacts, bank transactions, cashflow and VAT returns, depending on your access level.

We store the token FreeAgent issues in encrypted form; only the answers to your questions reach the chat.

What to ask about invoices, bank and VAT

Good questions to start with:

• Which invoices are overdue, by how many days, and who owes the most?
• How much is due to us in the next 14 days, and from which clients?
• Which payments into the bank account are still unexplained?
• Is there a payment in the bank that matches invoice 1077?
• How much came in and went out each month this quarter?
• How much is the next VAT payment, and when is it due?
• Which overdue invoices have FreeAgent’s automatic reminders switched off?
• Which clients paid late more than once this year?

Cases: chasing October’s money

The design studio in these examples is fictional, and so are its clients. Ask the same questions and you’ll get your own figures.

Who owes what

Start with the list: “Which invoices are overdue, and who owes the most?” FreeAgent can list overdue invoices on its own, and each one carries the amount still due and the due date.

9 invoices are overdue, £18,640 in total. Harbour Design owes the most: £6,200 on invoice 1061, 34 days late. Kestrel Foods has two, £2,400 on invoice 1077 and £1,500 on invoice 1089, 21 and 8 days late. The other 6 invoices add up to £8,540, none more than 15 days late. 4 of the 9 have automatic reminders switched off.

“We paid last week”

Kestrel Foods says they paid. The question to ask: “Is there an unexplained payment that matches Kestrel’s invoices?” A payment that reached the bank but was never explained in FreeAgent leaves the invoice showing as overdue.

Yes. On 15 October £2,400 came in from KESTREL FOODS LTD and is still unexplained. It matches invoice 1077 exactly. Invoice 1089 for £1,500 is unpaid. One more unexplained payment, £1,180 from M PATEL, doesn’t match any open invoice amount, so you’ll want to look at that one yourself.

Once that payment is linked to invoice 1077, the overdue total drops from £18,640 to £16,240.

Enough for the VAT bill?

Last, the payment that can’t slip: “How much is the next VAT payment, and do the invoices due before it cover it?” FreeAgent’s VAT returns carry the amount and the due date of each payment, and its cashflow shows what came in and went out each month.

The VAT for the quarter that ended on 30 September is £4,310, due on 7 November. Invoices due before then add up to £5,600 from three clients. September brought in £21,300 against £17,950 going out; October so far is £12,400 in and £9,870 out. If those three pay on time, the VAT is covered with £1,290 to spare, and Harbour Design’s overdue £6,200 would come on top.

What the AI can do in FreeAgent

Some of the follow-up the AI can do itself. Every email, payment match or draft is shown to you first, and nothing happens until you confirm.

• “Email Harbour Design a polite reminder about invoice 1061.” You see the recipient, subject and text before it goes, and you can edit them.
• “Switch on automatic reminders for the four overdue invoices that have them off.” The four invoices are listed first. FreeAgent switches reminders on only if you have a reminder email template set up.
• “Link the £2,400 from Kestrel Foods to invoice 1077.” You see the bank line and the invoice side by side, and the link is made after you agree.
• “Draft an invoice to Kestrel Foods for October’s work, £1,800, due in 30 days.” FreeAgent creates every new invoice as a draft. It stays one until you tell the AI to mark it as sent or email it.
• “Mark the VAT payment as paid, it left the bank this morning.” This only records the payment in FreeAgent, after your confirmation.