Bookkeeping Top Ten: Bookkeeping Mistakes That Cost You Money

Running a business is exciting — but messy books can quietly drain your time, energy, and profits.

Here are the Top Ten Bookkeeping Mistakes I see small business owners make (and how to avoid them).

1. Mixing personal and business funds

It’s tempting to just “grab the business card” or use your personal account for a quick purchase, but this makes tracking expenses a nightmare (and can cause tax headaches).

2. Not keeping all receipts

Even small expenses can add up. Without receipts, you risk losing deductions. Snap a picture and store them digitally.

3. Ignoring monthly reconciliations

If your bank balance doesn’t match your books, it’s a warning sign. Regular reconciliations catch errors early.

4. Misclassifying expenses

A meal with a client isn’t the same as office supplies — and the IRS cares about the difference.

5. Overlooking sales tax obligations

If you sell taxable goods or services, tracking and remitting sales tax correctly is non-negotiable.

6. Skipping regular financial reviews

Your profit & loss statement is more than just numbers — it tells you the story of your business. Don’t wait until year-end to read it.

7. Paying invoices late

Late payments damage relationships and may lead to interest or penalties.

8. Forgetting to track reimbursements

If you’re buying things for the business with personal funds and not reimbursing yourself, you’re losing money.

9. DIY bookkeeping beyond your comfort zone

There’s no shame in admitting you need help. Mistakes made now can snowball later.

10. Waiting until tax time to organize

The scramble costs you more — in both stress and potential missed deductions.

💡 Bottom line: Fixing mistakes costs more than preventing them.

👉 If you found yourself nodding along to more than a couple of these, we should talk. We specialize in making small business books accurate, clear, and easy to manage.