1. A negative loan balance
A liability showing less than zero means payments kept posting to the loan account after it should have hit zero, or every payment posted entirely to principal with interest never split out. Cause: no one reconciling the loan to lender statements. Fix: pull the lender's amortization history, re-split payments into principal and interest for the open period, and tie the ending balance to the statement. (Bonus: the interest you weren't booking is deductible, this error usually overstates profit.)
2. Undeposited Funds with a five-figure balance
The most common single item on this list, and usually paired with overstated income. The tray-and-deposit mechanics, the duplicate-income trap, and the full fix have their own guide: How to Fix Undeposited Funds in QuickBooks Online .
3. Accounts receivable that never shrinks
An AR aging full of invoices from two years ago means one of: payments were received but recorded as fresh income instead of applied to invoices (income now double-counted), invoices were issued twice, or the money is genuinely uncollected and nobody's chasing it. Fix: work the aging oldest-first, match payments to invoices, credit-memo the errors, write off the truly dead (with the tax treatment handled correctly). An honest AR number often drops dramatically, and what remains becomes an actual collections list.
4. Negative payroll liabilities
Payroll tax liability accounts below zero mean payments to the IRS/state posted against liabilities that were never accrued, or posted twice. This is the balance sheet error with teeth, because it means the books and the filed payroll returns disagree, and one of them is wrong. Fix: tie every liability account to the payroll provider's reports and the actual filings, quarter by quarter. If the filings themselves are off, that's an amend-and-fix conversation, not just a bookkeeping one.
5. Opening Balance Equity with any balance at all
OBE is scaffolding. QuickBooks parks offsets there during setup, and a finished setup zeroes it out. A persistent balance means setup shortcuts: accounts created with guessed balances, or migrations half-done. Fix: trace what created each amount and reclassify to where it belongs (owner contributions, retained earnings, or corrections). OBE on a balance sheet handed to a bank reads as 'nobody finished setting up these books', because that's what it is.
6. Mystery equity swings or a Retained Earnings that jumps around
Owner draws booked as expenses (deflating profit), contributions booked as income (inflating it), or prior-year edits made after the return was filed. Fix: owner money flows belong in equity accounts, draws, contributions, distributions, and closed years get locked so history stops moving. If profit on the books no longer matches profit on the filed return, document the bridge; your tax preparer will need it.
The pattern behind all six
Every one of these errors survives only where monthly reconciliation isn't happening, reconciliation is the audit that catches them at one month old instead of three years old. That's the real fix, and the reason 'we just need the balance sheet cleaned up' engagements always become monthly bookkeeping: the cleanup restores truth; the monthly close keeps it. Cleanup & Catch-Up Bookkeeping Services
Frequently asked questions
My accountant 'fixes' these every year at tax time. Isn't that enough?
That annual journal-entry sweep makes the return filable, it doesn't make your monthly reports true, and you're paying tax-season rates for bookkeeping repairs. Twelve honest closes cost about the same and give you twelve months of usable numbers.
Which of these actually matter to a lender?
All of them, but negative liabilities and unexplained equity are the fastest credibility killers, because they signal the file can't be trusted anywhere. Banks don't audit your balance sheet; they decline it.