An accounting clean up brings a company's books back to a state you can trust. Every bank, card, and loan account ties to its statement. Transactions are coded the same way every month. Receivables and payables list only what is really owed. And the P&L and balance sheet stop changing after you've read them. It's a one-time project, priced once, that has to happen before monthly bookkeeping can run on top of it.
Most guides stop at a checklist. This one also covers the order the work happens in, what to leave alone while it does, what drives the cost, and what "done" should mean. That last part is the one owners most often forget to ask about.
Three kinds of accounting clean up
"Clean up" covers three different jobs. Knowing which one you have is the first step to an accurate quote.
| Type | What you see | What the work is |
|---|---|---|
| Catch-up | The books stopped. The last reconciled month was a while ago. | Record and reconcile the missing months, oldest first. |
| Correction | The books are current but wrong. Balances don't match statements, or the P&L doesn't match how the business feels. | Find the errors, fix them with a record of every change, and re-reconcile. |
| Reconstruction | The records are missing or can't be relied on. | Rebuild the books from bank and card statements, payroll reports, and outside documents. |
Many files need some of each. A file that stopped eight months ago usually has errors from before it stopped, too.
Two real clean ups
From past Walden engagements, with the names left off.
A correction and a software move. A metro Atlanta railroad equipment distributor doing about $8 million a year ran on QuickBooks Desktop. Its CRM, its field service software, and its books were separate systems, data moved by copy and paste, and reports were built by hand in spreadsheets. We cleaned up 24 months of books in about 90 days, moved the company to QuickBooks Online, and connected HubSpot, Simpro, and QuickBooks so nothing gets retyped. The clean up found errors in years already filed, so we brought in a new CPA, who amended those returns.
A correction with nothing missing. Another company's books were current: zero months behind. But 24 months had been coded wrong. Payments recorded as owner distributions weren't distributions. Its project software, monday.com, didn't talk to QuickBooks, and the same customer had a different name in each system. Every month was entered, and the reports were still wrong.
Signs your books need a clean up
- Bank or card reconciliations haven't been done in months, or they're "done" but the reconciled balance doesn't match the statement.
- Balance sheet accounts that never move, or carry the wrong sign, like a negative payables balance or a loan that never goes down.
- A balance in Opening Balance Equity, or money sitting in Uncategorized Expense or an "Ask My Accountant" account.
- Customer payments piling up in Undeposited Funds, which QuickBooks Online now calls Payments to deposit.
- A receivables report full of invoices you know were paid, or a payables report full of bills you know were settled.
- Payroll or sales tax liabilities that grow every month instead of clearing.
- A P&L that changes after it was called final, or a CPA, lender, or buyer asking for numbers you can't produce.
You can check most of these yourself. Our free DIY Books Audit gives you ten AI prompts that run the same screens we run on a new file, in about two hours.
When the books reconcile and still mislead
A clean bank reconciliation doesn't make the numbers right. At the railroad distributor above, margin by order looked healthy. Once we matched each shipping invoice to the order it shipped, the gap showed: customers were paying about 1% to 2% of the order for shipping that cost the company 5% to 7.5%. Prices hadn't moved since 2022. Shipping fees and prices went up, the quote-to-sale close rate and revenue per customer held, and gross margin went from 12% to 38% in about six months. Fixing how a cost was recorded is what made the pricing decision possible.
Before you start: what to gather
The fastest clean ups are the ones where the records are ready on day one. Gather these for every period being cleaned up:
- Bank, credit card, and loan statements for every account, including closed ones.
- Payroll reports: registers and the quarterly filings.
- Sales tax returns and any notices from tax agencies.
- Your last filed tax return, so the cleanup starts from what your CPA reported.
- Loan and lease agreements, and anything you bought on financing.
- A list of every bank account, card, and entity, and the software that feeds the books (payroll, billing, job management, inventory).
- Admin access to the accounting file for whoever does the work, and the name of whoever approves payments.
What not to touch
Well-meaning owners make clean ups longer. Until someone has looked at the file:
- Don't delete transactions to make a reconciliation balance. The difference is usually telling you something.
- Don't force a reconciliation with an adjustment entry. It hides the error and the next person has to find it twice.
- Don't change a year your CPA already filed without asking them. Changing that year's income changes what was reported.
- Don't start a new company file to escape the mess before someone decides whether to repair or rebuild. A fresh file throws away history your CPA or lender may need.
The accounting clean up, step by step
The order matters. Accounts that tie to an outside statement get fixed first, because they're the only ones you can prove. Everything else gets checked against them.
- Assess and agree the scope. Which periods, accounts, and entities, which type of clean up, and what the finished product includes. Get it in writing.
- Reconcile bank and card accounts, month by month, oldest first. Every month ties to the statement before the next one starts. Coding errors get fixed as they turn up.
- Tie out loans and other liabilities. Loan balances match lender statements, with interest split out. Payroll and sales tax liabilities match what was filed and paid.
- Clean receivables and payables. Payments get matched to the invoices and bills they paid. What's left on the aging reports should be money really owed.
- Fix the classification. Uncategorized accounts emptied, the chart of accounts simplified, and the same kind of cost coded the same way every month.
- Sort out equity. Owner draws and contributions recorded as what they are, and Opening Balance Equity cleared.
- Review and produce corrected reports. A P&L and balance sheet for each covered period, reviewed by someone senior, not just whoever did the entries.
- Lock the periods. Set a closing date in the software so finished months can't change by accident, and agree what's still open and who owns it.
What "done" looks like
"The books are clean" is a claim. You can check it yourself, in your own accounting software, before you call the clean up finished:
- Every bank, card, and loan account is reconciled through the last covered month, and the reconciled balance matches the statement. Your software keeps a reconciliation report for each one.
- Balance sheet accounts match something outside the books: loan balances match the lender's statement, payroll liabilities match the payroll reports, and sales tax payable matches the returns.
- Receivables and payables aging reports list only money really owed.
- Uncategorized and suspense accounts are at zero, or every item left has an explanation.
- Opening Balance Equity is cleared, and owner draws and contributions are recorded as what they are.
- The P&L and balance sheet for each covered period have stopped changing.
Then ask whoever did the work two questions: what changed in any year your CPA already filed, and what's still open and who owns it.
"Done" doesn't mean every outstanding item disappears. A check written on the 30th and cashed on the 3rd is a legitimate reconciling item. What it does mean is that every remaining item is known, explained, and owned by someone.
How long an accounting clean up takes
Four things set the timeline:
- How many months are behind. Each month is a separate reconciliation for every account.
- Transaction volume per month, and how many bank accounts, cards, and entities there are.
- How messy the existing entries are. Correcting wrong entries takes longer than recording missing ones.
- How fast records come back. This is the one owners control, and often the biggest. A missing statement stops that account's work until it arrives.
For a sense of scale: our clean ups have taken no longer than 90 days so far, including the 24 months and the software move at the railroad distributor above. That assumes records come back when we ask for them. It also isn't the same as trusting the numbers: there, it was about six months before the books were solid enough to reprice on. Any honest timeline is a range with the records you owe written next to it.
What an accounting clean up costs
Clean ups are priced by the hour or as a fixed project quote. Hourly billing puts the risk of a messy file on you. A fixed quote puts it on the firm, which is why a good firm will want to look at the file before it quotes.
These are the things that move the price, in roughly the order they matter:
| Price driver | Why it moves the price |
|---|---|
| Months behind | Every month is another set of reconciliations for every account |
| Accounts and entities | Each bank, card, loan, and entity is reconciled on its own |
| Transaction volume | More transactions to match, code, and check each month |
| Correction vs. catch-up | Finding and fixing wrong entries is slower than recording missing ones |
| Payroll, sales tax, inventory, job costing | Each adds liabilities or schedules that have to tie to outside filings or counts |
| Missing records | Reconstruction from statements takes longer than fixing existing entries |
Walden quotes clean ups once, up front, as a flat project fee, and bills them separately from the monthly retainer. We don't publish a clean up price because two files with the same revenue can be months apart in effort. What we do publish is the monthly work that follows: Accounting runs $1,000 to $4,000 a month once the books are clean.
How to compare clean up quotes
Two quotes are only comparable if they cover the same scope. Ask each firm to put these in writing:
- Which periods, accounts, and entities are covered.
- Whether the price is fixed or hourly, and if hourly, whether there's a cap.
- Which deliverables you get at the end. Use the "done" list above.
- What records you need to provide, and what happens to the timeline if they're late.
- What's excluded: amended tax returns, payroll filings, inventory counts, and audit work are often outside scope.
Be careful with a fixed quote given without anyone looking at the file, and with any quote that doesn't say what "done" means.
Do it yourself or hire it out?
Our rule of thumb: you can usually clean up your own books if you have one or two bank accounts, you're a few months behind, payroll and sales tax are handled elsewhere and tie out, and no filed tax year needs to change. Start with the DIY Books Audit and fix what it flags.
Hire it out if you're more than a few months behind, if payroll or sales tax liabilities don't tie, if you run inventory, job costing, or more than one entity, if a filed year might change, or if a lender, buyer, or CPA has a deadline. Those are the clean ups where a wrong fix costs more than the clean up.
AI tools help with both. They can sort transactions and flag strange balances quickly. They can't tell you whether a balance is true without the outside statement it should match, and they can't decide how to treat a filed year. That still takes someone who knows what they're looking at.
Keep the books from needing another clean up
Books get messy one skipped month at a time. Five habits stop that:
- Close on a fixed date every month, not when someone gets to it.
- Reconcile every account monthly, including loans and payroll liabilities, not just the main bank account.
- Approve bills before they're paid, with the backup attached, so nothing gets paid twice or coded blind.
- Lock each month after it closes by setting a closing date in your accounting software.
- Review the balance sheet, not just the P&L. That's where old mistakes hide.
Our free Monthly Close Checklist is the 27-item list we close against. If you'd rather hand the monthly work off once the books are clean, that's what Walden Accounting does, and Walden Control adds a controller who checks it. For how the levels fit together, see our guide to fractional accounting services.