Insurance codes are a series of numbers and/or letters used by health plans to help determine how much healthcare providers are paid for different services, says About.com. Insurance codes are typically listed on medical bills.
There are three different coding systems used by medical billing companies, physicians and health plans, according to About.com. They are used to describe a diagnosis and the services provided.
The codes used by healthcare providers are called Current Procedural Terminology, or CPT codes, states About.com. They are developed by the American Medical Association to describe the services provided.
Medicare uses a different coding system called the Healthcare Common Procedure Coding System, or HCPCS, reports About.com. These codes are used to identify services, products and supplies not covered by CPT codes.
The World Health Organization provides the third type of coding system, called the International Classification of Diseases, or ICD, as stated by About.com. ICD codes are used to identify diagnoses or health conditions.