Bank reconciliation comes first. If your bank statements don’t match your accounting software, nothing else in your books can be trusted. Pull three to six months of bank statements and compare them line by line against what’s recorded in your software. You’re looking for missing transactions, duplicates, and amounts that don’t match.

Duplicates are one of the most common problems. They happen when transactions get entered manually and also downloaded through the bank feed. You end up with the same expense recorded twice, which inflates your costs and throws off your profit number. Missing transactions occur when someone forgot to record a check or the bank feed skipped something. Both problems show up immediately when you start reconciling.

Credit cards need the same treatment. Pull statements, compare line by line, find the gaps. If you’ve been ignoring credit card reconciliation for months, this part will take time. Don’t skip it.

Categorization problems are the next layer to address. Transactions coded to the wrong account make your reports useless. Office supplies sitting in professional services. Owner draws mixed in with payroll expense. Meals coded as supplies. Go through each expense category and scan the transactions. Anything that looks out of place probably is. Fix it now rather than explaining it to your accountant at tax time.

Uncategorized transactions need to be sorted. If your QuickBooks file has entries sitting in “Ask My Accountant” or “Uncategorized Expense,” each one needs a home. You can’t leave thousands of dollars floating in uncategorized and expect your profit and loss statement to tell you anything useful about your business.

Accounts receivable and accounts payable create their own problems when left unmanaged. Your books might show customers owing you money when they paid months ago. Or show bills as unpaid when you already wrote the check. Pull your aging reports and verify each open item against what actually happened.

Once reconciliations are clean, transactions are categorized correctly, and open items are verified, run your profit and loss and balance sheet. Does your cash balance match your actual bank account? Are there negative balances in accounts that shouldn’t have them? These are signs that something still needs work.

If this sounds like more than you want to handle on your own, you’re not alone. Bookkeeping cleanup is slow, detailed work that requires understanding what correct books should look like in the first place. What starts as a weekend project can turn into weeks when you’re not sure what you’re looking at.

Professional cleanup makes sense when your books are more than a few months behind, when you need accurate numbers for tax filing, or when you’ve received IRS notices suggesting your reported income doesn’t match your deposits. The cost of getting help is usually less than the cost of making business decisions with bad data or filing taxes based on numbers you can’t trust.

The goal isn’t perfect books. It’s books that reconcile to your bank accounts, categorize transactions in a way that makes sense, and produce reports you can actually use. A good small business bookkeeping service can get you there faster and with less frustration than trying to untangle months or years of problems yourself.