The three checks every Explanation of Benefits must pass

If you learn nothing else about reading an Explanation of Benefits, learn these three lines. They take a minute and they need no knowledge of your plan.

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

Every legitimate line satisfies all three. When one fails, you have found something objective, and that matters more than it sounds. A billing office can debate whether a service was preventive. It cannot debate whether four numbers add up.

Then do one more pass: add the line items and compare each column to the summary row the sender printed. Insurers print both views and they do not always agree, usually because a line was reprocessed and the total never followed.

Two definitions that make the lines usable:

• Allowed is the negotiated price and the base for everything. Billed is the list price and mostly a fiction for in network care.
• On a covered in network line, the gap between billed and allowed is the contractual write-off. That is the provider's discount, and it should never appear in your column.

Ten minutes with a calculator and last year's EOBs can be the best-paid ten minutes of your year.

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