Guides

A 30-Minute Monthly Bookkeeping Routine for a 1-5 Person Business

A simple monthly checklist to keep your books clean, plus quarterly tax dates and how long to keep records, sourced from the IRS.

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Not tax advice. For anything specific to your business, talk to an accountant.

Quick answer: Once a month, get every transaction into one place, categorize it, reconcile it against your bank statement, and file your receipts. Once a quarter, check what you owe in estimated tax. That's most of it for a small business.

The monthly checklist

Pick a fixed day, like the 5th of each month, and work through these in order.

1. Get last month's transactions in. Use your bank feed if it works. If it doesn't, download the statement as CSV and upload it. Our import guide shows the exact format QuickBooks, Wave, and Xero expect, and the bank statement converter can turn a CSV or Excel export into QBO, OFX, or QIF in your browser.
2. Categorize every transaction. Use the same categories every month so your year-end numbers make sense. Split anything personal out of business accounts.
3. Reconcile. Your ending balance in the books should match the bank statement's ending balance. If it doesn't, look for duplicates, missing transactions, or amounts entered with the wrong sign.
4. Match receipts. Attach or file a receipt for each expense. You'll need them as records (see below).
5. Review unpaid invoices. Follow up on anything overdue.
6. Run payroll checks if you have employees. Confirm last month's payroll and tax deposits went through and that PTO balances are up to date. Our PTO payout guide covers what you owe when someone leaves.
7. Look at one number. Profit for the month (income minus expenses). If it surprises you, find out why now, not in April.

Quarterly: estimated tax

If you expect to owe $1,000 or more in tax, including self-employment tax, when you file, you generally have to make estimated payments (IRS Publication 334). For calendar-year taxpayers, the IRS due dates are (IRS estimated tax FAQ):

Add these four dates to your calendar now.

How long to keep records

From the IRS record-keeping page:

• Generally 3 years after you file the return the records support.
• 6 years if you leave out income worth more than 25% of the gross income on your return.
• Indefinitely if you don't file, or file a fraudulent return.
• Employment tax records: at least 4 years after the tax is due or paid, whichever is later.
• Asset records: until the limitation period runs out for the year you dispose of the asset.

Check with your insurer or lenders before you throw anything out, since they may require longer.

Spreadsheet or software?

A spreadsheet is enough when you have few transactions and no employees. Our small-business bookkeeping sheet is built for Excel and Google Sheets.

In our view, once the spreadsheet starts eating real time each month, or you hire, accounting software with a bank feed is worth a look. Compare current plans on each vendor's site:

• Try Wave
• Try QuickBooks Online
• Try Xero
• For payroll and PTO tracking: Try Gusto

Sources: IRS. Last checked Oct 11, 2026.