There are three ways to get QuickBooks Online into Claude, and picking the wrong one costs you an afternoon. This walks through all three, then sets up the one most people should use.
First, which one are you installing
Intuit's own connector, inside Claude. One click from the Connectors panel, free with a QuickBooks subscription. It covers profit and loss, cash flow, industry benchmarking, transaction import, and the sales side: invoices, estimates, payment links, customers, products. Intuit states its use cases are limited to that list, and it is not offered to Canadian QuickBooks companies.
Intuit's open-source server, from GitHub. Full create, read, update and delete across 29 record types and 11 reports. It runs on your own machine over stdio, so you need an Intuit developer account, an OAuth app, API keys, and a process kept running. One company per setup, and it cannot work from Claude on the web or on a phone.
Caribooks. Hosted, so nothing runs on your machine. 209 tools and 35 reports across the whole ledger, several companies under one subscription, English and French, and it works on Claude web and mobile including the free plan.
If you only need a profit and loss and the ability to send invoices, stop reading and install Intuit's connector. It is free and it will do the job. The rest of this guide is for people who need the balance sheet, aged receivables, journal entries, vendors, bills, or more than one company file.
Setting up Caribooks
1. Create the account and connect QuickBooks. Sign in at caribooks.com, then connect a company from the portal. This is the standard Intuit authorization screen, the same one any QuickBooks app uses. No developer keys, no API console.
2. Add the connector to Claude. The portal gives you a prefilled install link. Claude opens with the connector ready; click Add, then authorize Caribooks when Claude asks. About two minutes.
3. Set tool permissions once. On your first request Claude asks permission for each tool it wants to call. Choose "Always allow" so you are not interrupted on every question. You can also set this ahead of time under Customize, then Connectors, then Caribooks, then Tool permissions.
4. Check what access you granted. Every connection starts read-only. Nothing can write to your books until you switch that company to full access yourself, from the portal. Leave it read-only for the first week. You will learn what the assistant is good at before it can change anything.
The first five things worth asking
Start with questions you already know the answer to. It is the fastest way to build trust in the numbers, and to catch a company file that is connected but not the one you meant.
- "What invoices are overdue, and by how many days?"
- "Show me profit and loss for last quarter compared to the same quarter last year."
- "Which customers account for most of my receivables right now?"
- "What changed in the books since Monday?"
- "Pull the aged payables and tell me what is due in the next 14 days."
The fourth one is the one people underrate. A running answer to "what changed" is something the QuickBooks interface makes genuinely tedious to assemble.
When to turn on write access
Turn it on when you have a task you would otherwise do by hand and can check afterwards. Drafting an invoice from an email thread is a good first one, because the result is visible in QuickBooks and easy to correct. Categorizing a batch of expenses is a good second one.
Two things stay true no matter what you enable. Sending a document by email, voiding, and deleting each require an explicit confirmation in the conversation. And write access is per company, so a bookkeeper can keep nine client files read-only while working in the tenth.
If something does not connect
The most common cause is being signed in to the wrong Intuit user. Disconnect fully from the Connectors panel, wait a moment, and reconnect once. Reconnecting immediately after disconnecting tends to fail.
If Claude answers from stale numbers, confirm the connector still shows as active in your settings. A connector that has lost its session usually looks fine until you read the answer closely.