Where to Find Medical Billing Codes

Diagnosis Codes

Diagnosis codes are known as ICD-9 codes, for International Classification of Diseases, 9th Version. You would get those codes out of an ICD-9 code book. This book is thick because it is so comprehensive. You want to get your information from the code book as opposed to getting it online because the book provides explanations of how to properly order the diagnoses for a patient's claim. Ordering diagnoses is very important in getting patient claims paid properly.

Procedure Codes

Procedure codes are known by two names, depending on who you talk to. Generally, they're known as CPT-4 codes, which stand for Current Procedure Terminology, Version 4. Some people will call procedure codes HCPCS codes, which stands for Healthcare Common Procedure Coding System. These are level II codes which mainly describe supplies, products and pharmaceuticals, although there are a few procedure codes in this system as well..

There are also CPT-4 code books that are geared towards certain specialties such as radiology or endoscopic surgery. These are crucial for those departments to have because they give more detailed explanation of how and when to use these codes as opposed to most general CPT-4 codes, which will give some information but not in the same detail as the specialty-specific books.

Revenue Codes

For hospital bills, a revenue code is needed for every procedure that's on a bill. Revenue codes denote either which area of the hospital a service was provided in or the general type of procedure that was performed. You would get this information out of a book designed to explain the billing form a hospital uses, in this case a UB-04 manual. It gives the explanation of every single revenue code, as well as extra information for when to use them, since many procedures can use different revenue codes, depending on a number of circumstances including where the procedure was performed.


Modifiers are two-digit additions to some procedure codes that give a little bit more information on which part of the body a procedure was performed, or what might have happened during that procedure. You can get a list of modifiers out of both a CPT-4 book and a UB-04 manual, but in this case the best place to get information about modifiers is from Medicare, or the CMS (Centers for Medicare and Medicaid Services). This is because Medicare is the main insurance type that requires modifiers; most other insurance carriers don't want this information. Medicare gives detailed instructions on how to use these modifiers, which is very helpful because modifiers can be complicated.

Condition and Occurrence Codes

Condition codes are two-digit codes that try to explain the condition a person was in when they sought treatment. Occurrence codes are two-digit codes that describe what might have caused a patient's distress, such as a work injury or car accident. These codes are not expected to be on every claim. You would get these codes out of either the UB-04 manual if you're billing for a medical entity, or a HCFA-1500 manual, which describes the billing form physicians use. All medical bills require certain codes before you can send them out. Otherwise, they won't be paid by the insurance companies. There are a number of codes needed, and there are even different ones depending on whether you're a physician or another medical professional . While you can find some of the codes on the internet, there are specific books you need to get the codes you want.