ICD-10 CODES
What is an ICD-10 code on my medical bill or EOB?
An ICD-10 code describes the reason for your care — a diagnosis, symptom or condition — on a medical claim. A CPT code says what was done; the ICD-10 code says why, and insurers look at both when deciding whether to pay.
Why it’s confusing
ICD-10 codes look cryptic — a letter, then numbers, often with a decimal point — and they can be alarming when the description printed beside one sounds more serious than anything you were told.
A code can also reflect what was being checked, not what was found. A test ordered to rule something out may carry a code for the symptom or the suspected condition.
How to read it
In the US, diagnosis codes on claims use ICD-10-CM. CMS notes the change from ICD-9 to ICD-10 happened on October 1, 2015, and the code set is updated every year from October 1.
ICD-10-CM codes start with a letter, followed by numbers, and can run up to seven characters. Broadly, the first three characters name a category and the characters after the decimal add detail.
If a description on your bill or EOB doesn’t fit your visit, ask. A wrong diagnosis code can make an insurer deny a claim, and the provider can correct it.
What it does not mean
- That you have been diagnosed with what the description says. Codes can record symptoms or conditions being ruled out.
- That a code tells you how serious something is. It is a classification for records and billing.
- That the code can’t be wrong. Coding errors happen and can be corrected by the provider.
Where you’ll see it
- Itemized bills and claim forms, often labelled “diagnosis” or “Dx”.
- Insurance EOBs and denial letters.
Questions worth asking
Ask your doctor’s office
- Why was this diagnosis code used for my visit?
- Can it be corrected if it doesn’t match what happened?
Ask your insurer
- Was the claim denied because of the diagnosis code?
Seeing a diagnosis code you don’t recognise? Attach the bill or EOB, and Clariti will explain what the document says.
Common questions
- What is the difference between ICD-10 and CPT codes?
- ICD-10 codes describe the diagnosis or reason for care. CPT codes describe the service or procedure that was done.
- Can a wrong ICD-10 code cause a claim denial?
- Yes, it can. If the code doesn’t match the care, ask the provider’s office to review it and resubmit the claim.
- Does a code on my bill mean I have that condition?
- Not necessarily. Codes can record symptoms or a condition being ruled out. Ask your doctor what was found.