Start with bank reconciliations. Before you worry about categorizing transactions, make sure every bank and credit card statement matches what’s in your accounting software. If you don’t have accounting software set up, that’s step zero. Download all your statements going back to wherever your books are clean. If they’ve never been clean, go back to the beginning of the year or when your business started.

Gather everything before you dive in. Bank statements, credit card statements, invoices you’ve sent, receipts for major purchases, payroll records, loan documents. The biggest time sink in catching up is stopping to hunt for a missing statement. Get it all organized first and save yourself hours of frustration.

Work month by month in order. Don’t skip around trying to fix the easy months first. Start with your oldest incomplete month and work forward. Each month should end with reconciled accounts before you move to the next. Jumping around creates gaps and duplicate entries that are harder to find later.

For each month the process is the same. Import or enter transactions, categorize them, reconcile bank and credit card accounts, and review for anything missing. A payment that shows on your bank statement but not in your books means something got lost. A deposit you can’t explain might be a customer payment that never got recorded properly.

Use your software’s automation features. QuickBooks and Xero both let you create bank rules for recurring transactions. Your monthly software subscriptions don’t need manual categorization every time if you’ve set up rules. This saves significant time when you’re processing months of transactions at once.

Don’t aim for perfection right now. The goal is getting caught up with reasonable accuracy. Use broad categories that make sense and stay consistent. You can always refine the details once you’re current. Spending twenty minutes deciding whether something is office supplies or computer expense is not a good use of time when you’re six months behind.

Know when professional help makes sense. If you’re more than six months behind, if there are transactions you don’t understand, or if you need financials soon for an investor or lender, bookkeeping cleanup from someone who does this regularly will save you time and likely produce better results. The cost of cleanup is usually less than the value of your time spent struggling through it.

Many business owners who work with a startup accountant for the first time are coming out of exactly this situation. They fell behind, caught up once, then fell behind again because they never built a system to stay current. Once your books are clean, set a recurring time each week or month to keep them that way. Thirty minutes weekly beats a weekend marathon once a year.