Playbook
How we run a startup month-end close in Claude with QuickBooks
This is the month-end close we run for startup clients. Claude is connected to the client’s QuickBooks Online, bank, and payroll provider, plus the shared drive where the close files live. It does the pulling, matching, and first drafts. A person makes every judgment call and approves every entry before anything posts.
Below is the workflow, with numbers from one real September close for a growth-stage B2B subscription company (about 50 customers, a payroll provider, and US and international contractors). The company stays anonymous.
The rule that makes this work: Claude proposes, a person approves. Nothing posts to the general ledger without a human looking at it.
What you need connected
- QuickBooks Online as the general ledger
- The bank (and cards, if separate) for transaction feeds
- The payroll provider’s register or export
- A shared folder for the close checklist, schedules, and last month’s notes
You don’t need a new close tool. Claude reaches these through connectors under the company’s own logins and permissions.
Step 1: Categorize the pending transactions
Claude pulls every uncategorized transaction from the bank feed and proposes an account (and department, where the company tracks them) for each one. It doesn’t post anything. It writes a review file with its reasoning.
In the September close it worked through 37 pending bank transactions:
| Result | Count |
|---|---|
| Changed from the QuickBooks prefill | 7 |
| Kept the prefill | 14 |
| Flagged for a person to decide | 13 |
| Held back for the payroll reconciliation | 5 |
The 13 flags are the useful part. Claude is good at knowing when a transaction needs context it doesn’t have, like a payment to a related entity or a vendor it hasn’t seen before. Those go to a person with a short note on why.
Step 2: Reconcile payroll to the provider’s export
Payroll is where startup books drift the most, so it gets its own step. Claude takes the payroll provider’s full export, which was 1,542 lines in September, and builds the entries split by account and department.
That month it produced 15 payroll-related transactions (14 expenses and one refund deposit) and mapped 14 new charge types the provider had introduced. Then it tied September’s payroll debits in the bank to the export. They matched exactly.
Step 3: Tie out the statements
Before anyone reads the numbers, Claude checks they agree with each other. In this close it confirmed that the P&L summary tied to QuickBooks net income for every month from January 2025 through September 2026, not just the current one. Re-checking prior months catches back-dated edits that would otherwise surface in diligence.
It also compared billing data to the ledger and found 17 invoices that no longer existed in the billing system, most likely voided or reissued after a move to a new billing tool.
Step 4: Surface the exceptions
These are the items Claude raised in September, described generally:
- A vendor refund booked as income. Claude proposed reclassing it against the original expense. A person approved it.
- A possible duplicate payment. A wire matched a contractor’s payroll-provider payment to the cent. Flagged for a person to confirm with the contractor.
- Customers billed in two systems. Some customers had invoices in both the old and new billing tools during the migration.
- A placeholder invoice addressed to the company’s own email.
- A refunded contractor payment. Claude booked both sides so they net to zero, instead of leaving a stray credit.
None of these are exotic. They’re the things that pile up quietly when nobody has time to look, and they’re exactly what an investor’s diligence team finds first.
Step 5: Draft the month-over-month review
Claude adds the new month to the reporting pack and writes “needs your review” notes on anything that moved in a way that needs explaining. In September that was 8 items. One example: monthly recurring revenue looked overstated because one-time invoices were sitting in a recurring revenue account.
A person then turns the useful notes into commentary for the founder. Claude’s draft gets you most of the way. The judgment about what matters this month is still a human call.
Step 6: Write down what changed
The last step is the one most teams skip. Claude updates the close checklist and notes with anything new this month: new charge types, new vendors, the reclass rule for refunds. Next month’s close starts from a better playbook than this one did.
How long it took
From kickoff to the finished close summary: about an hour and a half of working time, most of it spent reviewing Claude’s flags. It was about two hours including the follow-up reclass and updating the playbook.
What Claude doesn’t do
- Post entries without approval
- Decide how to treat related-party or unusual transactions
- Contact vendors, contractors, or customers
- Sign off on the close
Automation nobody checks just makes mistakes faster. Each step above ends with a person reviewing the output.
Why this is harder than it looks
The outline above fits on one page. Running it well every month is the hard part: rules tuned to each company’s chart of accounts and vendors, review checks that catch what a model will confidently get wrong, and a close checklist that gets sharper every month. That setup is most of the value, and it’s the part we build and run for clients.
If you want this running on your books, or set up for your in-house finance team, book a 30-minute intro.
Want this running on your books? Book a 30-minute intro.