How to make sense of the medical math

You open a statement from your insurer to discover that you were charged $1,200 for a 30-minute doctor’s appointment. That’s a pretty impressive price tag for someone checking your blood pressure and asking how you’re feeling. 

Then you spot five glorious words: “This is not a bill.” 

That could be reassuring, except the document looks suspiciously like a bill. Meet your Explanation of Benefits.

An EOB is not a bill, so what is it?

Despite its intimidating appearance, an Explanation of Benefits (EOB) isn’t a request for payment. An EOB typically shows the medical services you received, what your provider charged, what your insurance covered, and what you may owe. 

Your healthcare provider usually sends the actual bill after insurance processes the claim. The EOB just gives you a chance to see how the insurer arrived at those numbers. 

Of course, knowing that an EOB isn’t a bill doesn’t make it any easier to decipher. Between the original charges, insurance discounts, and your share of the costs, there’s a lot of math happening behind the scenes. 

So how does a $1,200 doctor’s appointment turn into a $60 bill? And what happens when those numbers don’t add up? 

Decoding the numbers without a finance degree

Let’s revisit that $1,200 doctor’s appointment to see where the money actually goes. (This example is for demonstration purposes only.)

• Amount billed: $1,200. What your doctor charged.
• Allowed amount: $300. The maximum amount your plan recognizes for a covered service, typically based on a negotiated rate with an in-network provider. 
• Insurance adjustment: $900. The discount your in-network provider usually writes off. 
• Insurance paid: $240. What your insurer actually paid. 
• Patient responsibility: $60. What you may owe.

Not quite the $1,200 financial disaster you were expecting. Of course, deductibles, copays, and coinsurance can change the final numbers. Your actual share depends on your plan. 

When the EOB and your bill look different

Your EOB says $60, but your doctor’s office sends a bill for $260. Did someone forget how math actually works? 

Before assuming you’re being overcharged, know that the difference could come from a processing delay, a separate service, or an actual billing error. Start by comparing your EOB and bill. Check the dates, services, charges, insurance payments, and your share of the costs. Watch for duplicate charges, services you never received, or insurance payments that vanished into thin air. 

If something doesn’t add up, call your provider’s billing department first. Ask whether your insurance payments and adjustments were applied correctly. If the problem is with the EOB itself, contact your insurer. You may need to request a correction or appeal a denied claim. 

The bottom line is that your EOB isn’t a bill. It’s your chance to check the math before handing over your money. Seeing a doctor is already expensive enough without paying more than you actually owe.