The monthly close: a bookkeeping checklist for small companies

By the Zipple team · Updated October 28, 2026

Closing the books every month takes an hour when it's routine and days when it's left to tax season. The point is simple: at the end of each month, your books match your bank to the cent.

The checklist

1. Download the bank statement for the month from every business account and card, as CSV and PDF.
2. Import every transaction. Check the first and last dates so nothing is missing between months.
3. Categorize each line: revenue, software, contractors, fees and so on. Split mixed payments.
4. Mark owner transfers. Money you put in or took out isn't income or expense. For a foreign-owned LLC these totals go on Form 5472.
5. Reconcile: opening balance plus everything in the month must equal the closing balance on the statement. If it doesn't, look for missing, duplicated or reversed transactions.
6. Attach documents: invoices for large expenses, contracts, and W-9 or W-8BEN forms for new contractors.
7. Lock the month and look at the P&L and cash: anything unusual is easier to explain now than in eleven months.

Common mistakes

• Recording Stripe payouts as revenue instead of the gross sales minus fees.
• Counting transfers between your own accounts as income.
• Paying business costs from a personal card and forgetting to record them.
• Changing a closed month without noting why.

This guide is general information, not advice for your situation.