Why the insurance check doesn't match the EOB

Every insurance payment has to satisfy one simple equation: the check total equals the sum of the claim payments on it, plus or minus any adjustments the payer made at the check level. When the numbers on the EOB don't satisfy that equation, the cause is almost always one of the five below.

1. The check covers more than one patient

Payers bundle claims. A single check can pay for a dozen patients across several pages, and the payment for one claim on page one looks nothing like the check total on page four. If you're comparing one claim to the whole check, they won't match. That's expected, not an error.

What to do: add up the plan-paid amount for every claim on the EOB, across all pages, before you compare against the check.

2. The payer took money back (recoupment or offset)

If a payer decides it overpaid an earlier claim, it often doesn't ask for a refund. It deducts the overpayment from the next check instead. The EOB shows the current claims paid in full, and then a separate line, usually near the end, that subtracts the recovered amount. On an electronic remittance (835) this shows up as a provider-level adjustment; on paper it's often labeled as an offset, a recovery, or a prior-overpayment deduction.

What to do: look for a negative line that isn't tied to any of the claims being paid. The recovered amount has to be applied to the original claim it came from, not to the patients on this check.

3. Interest or a check-level adjustment was added

Some payers add prompt-pay interest when a claim was paid late, which makes the check a little larger than the claims add up to. Others apply small check-level corrections that don't belong to any one claim.

What to do: find the interest or adjustment line and account for it on its own. It isn't a payment on any patient's procedure.

4. The claim was split or partly paid

A payer may pay some procedures on a claim now and pend or deny the rest, or pay one claim across two checks. The EOB in front of you is then only part of the story, and the claim stays open after you post it.

What to do: check each procedure line's status. Lines with nothing paid and a denial or pending reason code need follow-up, not a write-off.

5. A number was read or keyed wrong

The least interesting reason, and the most common one on scanned paper. A 3 that was really an 8, a line skipped on a dense page, a patient-responsibility amount typed into the plan-paid column. Each one leaves the check unbalanced by a specific amount.

What to do: check each line's own math first. For every procedure, the billed amount should equal the write-off plus the plan-paid amount plus the patient's portion (deductible, coinsurance, copay). The line that breaks that rule is usually the line that was misread.

A quick reconciliation routine

1. Check every line. For each procedure, billed = write-off + plan-paid + patient portion.
2. Total each claim. Each claim's line totals should match the claim totals printed on the EOB.
3. Sum all claims. Add up the plan-paid amount for every claim on the EOB, across every page.
4. Apply check-level lines. Subtract recoupments and offsets, add interest.
5. Compare to the check. If it still doesn't match to the penny, don't post yet. The difference tells you how much to look for.

In Open Dental, the check becomes one insurance payment with each claim's payment attached to it, so posting is much easier once the EOB balances on paper first.

How Argus handles it

Argus runs this routine on every EOB automatically. It extracts each line, re-checks the math on every line and claim with exact-decimal arithmetic, and reconciles the claims against the check total. If anything doesn't add up, it stops and shows where the difference is, so a person can review it before anything posts to Open Dental.