Bank reconciliation, explained

Start with the example, because the definition follows from it

A company’s QuickBooks Online checking account shows $12,460.00 at the end of the month. The bank statement for the same account, same date, shows $12,160.00. The two numbers are $300 apart, and nothing has gone wrong yet.

Working through the account turns up four things. A $750 deposit was recorded on the 30th and did not reach the bank until the 2nd. A $420 check was written and mailed but has not been presented. The bank charged a $30 service fee that nobody entered. The bank paid $60 of interest that nobody entered either.

Two of those belong on the bank’s side and two belong on the books’ side, and getting that split right is most of what people get wrong. Start at the bank’s $12,160.00, add the $750 that is in transit, subtract the $420 that is outstanding, and the adjusted bank balance is $12,490.00. Start at the book balance of $12,460.00, subtract the $30 fee the bank already took, add the $60 of interest the bank already paid, and the adjusted book balance is $12,490.00.

Both sides land on the same figure, and every dollar of the original $300 gap has a name attached to it.

That is a reconciliation. Not two numbers being equal, but every difference between them being identified and explained.

The formula, in the only form worth memorizing

Adjusted bank balance = statement balance + deposits in transit - outstanding payments.

Adjusted book balance = register balance + items the bank recorded that the books did not - items the books recorded that the bank charged against you.

The reconciliation is complete when those two adjusted figures agree. The asymmetry between the two lines is the whole logic of the exercise: the bank side gets adjusted for timing, and the book side gets adjusted for information. Things the bank has not seen yet go on the bank side. Things the bank knew before you did go on the book side.

The four differences that are not errors

Deposits in transit are payments recorded in the books that the bank has not yet credited. A deposit dropped on a Friday afternoon is real money and a real accounting entry; it just is not on a statement that closed the same day.

Outstanding checks and payments are the mirror image. The check was written, the payable was cleared, the expense was recorded, and the payee has not cashed it. An outstanding check is not a missing transaction and it should not be voided to make a reconciliation easier. Voiding it puts an expense back that was genuinely incurred.

Bank fees, service charges, and returned-item charges flow the other way. The bank knew about them at the moment they were assessed; the books find out when someone reads the statement. Until they are entered, the register overstates cash.

Interest and bank-side credits are the same problem with the opposite sign. Small enough to ignore for years, which is exactly why they accumulate into an unexplained difference nobody can trace.

Everything else that shows up in a reconciliation is an error, either yours or the bank’s, and needs correcting rather than adjusting for.

Errors on the bank’s side, which do exist

Banks post the wrong amount, credit the wrong account, and duplicate a debit occasionally. It is rare enough that assuming it first will waste a day, and common enough that refusing to consider it will waste a week. The test is documentary: if the check was written for $1,240 and the statement shows $1,420, the check itself settles the argument. Errors on the bank’s side get adjusted on the bank line of the reconciliation and then reported to the bank, because the correction has to arrive on a future statement or the same gap reappears next month.

Errors in the books, which are most of them

A transposed digit. A payment entered twice, once by hand and once through the bank feed. A deposit dated to the wrong month. A transaction categorized to the right amount and the wrong account, which does not break the reconciliation at all and is the reason a clean reconciliation proves less than people think.

The useful diagnostic is the shape of the difference. A gap that exactly matches a single line on the statement is almost always one transaction, miskeyed or missing or duplicated. A gap that is an uneven figure spread across many cents is usually several small items stacked together, and it is faster to compare statement totals period by period than to hunt transaction by transaction.

Why an account that reconciles can still be wrong

Reconciliation tests one thing: that the cash recorded in the books matches the cash the bank holds, once timing is accounted for. It says nothing about whether the money was recorded in the right place.

A $4,000 owner draw coded to contract labor reconciles perfectly. So does a loan repayment coded entirely to interest expense, an equipment purchase expensed instead of capitalized, and a customer payment applied to the wrong invoice. In every one of those cases the cash moved, the amount is right, the date is right, and the financial statements are wrong.

Three failures survive a clean reconciliation reliably enough to be worth checking for on their own. Duplicate transactions where both copies were reconciled in the same period, which nets to zero on the reconciliation screen and doubles an expense on the profit and loss. Miscoded transactions, which never touch the reconciliation at all. And a wrong opening balance, where the account has reconciled cleanly every month since the file was created and started from a figure that was never verified against a statement.

The format, and why the spreadsheet version still exists

A bank reconciliation statement, in its traditional form, is two columns. The bank column starts at the statement balance and adjusts for timing. The book column starts at the register balance and adjusts for information. Both end at the same adjusted figure, and the supporting detail lists every reconciling item individually so the next reader can follow it.

QuickBooks Online performs the same logic inside its reconcile screen and produces a report at the end, which is why most people working in it never build the two-column statement by hand. It is still worth understanding, for two reasons. When the reconcile screen refuses to reach zero, the two-column layout is what tells you which side the problem is on. And for accounts QuickBooks does not connect to, which still includes plenty of merchant accounts, escrow accounts, and older loans, a spreadsheet is the only place the reconciliation exists.

What a reconciliation should leave behind

A completed reconciliation should be reproducible by somebody who was not there. That means the statement it was performed against is retrievable, the reconciliation report is saved, the reconciling items are individually identified rather than summarized into one adjusting figure, and no entry exists whose purpose was to make the difference disappear.

That last one carries the most weight. QuickBooks Online will let you close a reconciliation with an unexplained difference by posting it to a miscellaneous account. Doing so records that the books and the bank disagree and that nobody found out why, and it moves the problem into next month’s beginning balance, where it is harder to trace.

When the difference has been there for a while

A reconciliation that has not tied for one month is a search. A reconciliation that has not tied for a year, or one that has been forced to zero repeatedly, is a different job: the break has to be found in the period it actually happened, and every reconciliation after it has to be rebuilt on the corrected figure. A bank balance that won’t reconcile covers how to find the period, and the reconcile screen in QuickBooks Online covers the mechanics once you know which month you are rebuilding.

Walking back through closed periods, correcting the underlying transactions, and re-reconciling each month in order is cleanup work, scoped by how many months back the break sits:

$99 per month of backlog

Once the file ties, a monthly close reconciles every account against a real statement each month, which is the only thing that stops this from rebuilding. Both are priced in full on the pricing page.