When the numbers on your EOB don't add up

The four numbers on this line add up to $160. The line says you owe $200.

That is the whole finding. No plan knowledge, no interpretation, no argument about what your benefits cover. Either the columns add up or they do not.

This is the first family of billing error and it is the one to start with, because the checks are free and the findings are impossible to talk you out of.

Three things to add up on any Explanation of Benefits:

• Billed should equal allowed, plus the network discount, plus anything not covered.
• Allowed should equal what the plan paid plus your share.
• Your share should equal deductible plus copay plus coinsurance.

Then add the line items and compare them to the summary row the insurer printed. Those two views disagree more often than you would expect, usually because a line was reprocessed and the total never followed.

One tip on what to ask for. When the arithmetic fails, ask for a corrected document rather than a refund. If the EOB does not agree with itself, the insurer needs to reissue it, and the provider's balance should be recalculated from the corrected version. Asking for money first skips a step, and skipped steps get denied.

General information, not legal, medical or financial advice. Every plan is different, so check the details against your own plan documents.