Understanding These Health Insurance Codes Could Help You Spot Errors and Avoid Overpaying

Cracking these healthcare codes could help you save on healthcare costs.

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Updated May 28, 2024
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Many people worry that despite health insurance coverage, they might get stuck paying an expensive bill after a visit to the doctor.

Even if you call the doctor’s office and make sure your insurance will cover the provider, it's still possible to end up paying some of the cost.

In some cases, the amount you owe is small. But billing errors can lead to a costly situation. And such errors are more common than you might think.

Understanding the most common insurance codes and how they work can help you avoid wasting money by paying hundreds more than you actually should.

What are insurance codes?

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When you visit a medical professional, they will bill your insurance provider with a specific code related to your appointment. The code describes what happened during the visit. Each visit may have multiple codes, especially if you had lab tests, imaging, or similar services.

Insurance companies use these codes to decide how much of the service they will cover before the rest of the bill is passed on to you. Unfortunately, it's not uncommon for errors to creep into this process.

The American Medical Association (AMA) says error rates at insurance companies can reach nearly 20%. Unless you notice and dispute such errors, you could end up on the hook for a larger percentage of the bill than you expected.

Next are a few key types of health insurance coding systems you need to know.

Current Procedural Terminology

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Current Procedural Terminology (CPT) is the official name of the coding system used by health care billing departments.

There are three main levels of CPT codes: Category I, Category II, and Category III. Category I represents the most common code and is likely the one you will see.

The Category I codes fall into six basic categories:

  • Evaluation & Management (99201–99499)
  • Anesthesia (00100–01999; 99100-99140)
  • Surgery (10021–69990)
  • Radiology Procedures (70010–79999)
  • Pathology and Laboratory Procedures (80047–89398)
  • Medicine Services and Procedures (90281–99199; 99607)

Here are some common CPT codes:

  • 99213 and 99214: Established patient office visit
  • 99201-05: New patient office visit
  • 80053: Organ or disease-oriented panels
  • 93010: Cardiography procedures
  • 71045: Diagnostic radiology (diagnostic imaging) procedures of the chest

Healthcare Common Procedure Coding System

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If you have Medicare, your codes will be based on another coding system: The Healthcare Common Procedure Coding System.

There are two subtypes: Level I and Level II:

  • Level I refers to codes similar to those of the CPT system.
  • Level II refers to codes unique to Medicare itself and used for services, products, and supplies that don't fall under CPT codes. You can download a list at the Centers for Medicare & Medicaid Services website if you need to check one of these codes.

International Classification of Diseases

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The International Classification of Diseases is a coding system describing your illness or diagnosis. The appropriate CPT code is then linked to this disease code.

The World Health Organization (WHO) helped create these codes, which are used globally.

Here are some common disease codes:

  • U07.1: COVID-19
  • G89.11: Acute pain due to trauma
  • I10: Essential (primary) hypertension
  • J301: Allergic rhinitis due to pollen

How to prevent errors

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Billing errors can happen if the health care provider submits the wrong code. The insurance company might refuse to pay for a treatment when this happens.

For example, let’s say you have pain and swelling in your ankle and the doctor orders an X-ray. If the medical provider’s billing department codes your illness as the flu, the insurance company might deny paying for your X-ray because it’s unrelated to flu treatment.

While it's impossible to eliminate the risk of such errors, you can greatly reduce their impact by taking some key steps.

For example, when you visit the doctor's office, write down what happens. If there's a physical exam along with bloodwork, make a note of both the exam and the bloodwork. Some doctors also have an online system that lets you see their notes, which should include what occurred during the visit.

After receiving a medical bill, go through it and see if anything is listed as not covered. You may have to ask your provider for a copy of the superbill, which is a document created specifically for insurance companies.

The superbill should have all of the billing codes used during the visit. Match the codes with your notes from the actual visit.

How to fight back against insurance error codes

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Contact the billing department to explain the discrepancy if you notice an error. Then, ask them to review and refile the claim with insurance.

Set a reminder to follow up in a couple of weeks to ensure that the mistake has been fixed. It can take several weeks for the issue to be resolved.

Unfortunately, medical billing departments can be notorious for giving patients the runaround, so you may have to be persistent and call back a few times. Visiting them in person can expedite the process if no one calls you back.

You can also ask for a patient advocate or ombudsperson to act as a liaison between you and the billing department. However, only some hospitals will have one of these.

If the billing department is too far away to visit, contact the physician via email or social media.

You can also contact your insurance company and ask for a three-way call between yourself, the billing department, and the insurance company. Sometimes, this will be more effective than just calling the billing department yourself.

Bottom line

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Medical billing errors happen more often than many people think. These mistakes can be costly for patients.

So, to eliminate some financial stress, keep a close eye on what happens during your appointment and scan your bill closely when it arrives. Doing so might save you a lot of cash.

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Author Details

Zina Kumok

Zina Kumok is a freelance personal finance writer specializing in student loans, credit, personal loans, mortgages, investing, and more. As a former newspaper reporter, she has covered murder trials, the Final Four, and everything in between. She also paid off $28,000 worth of student loans in three years.