When to use modifier 33 for preventive care

July 25, 2011

Modifier 33 has created much confusion in the coding and billing world. Learn why.

Key Points

Q: I recall seeing modifier 33 for a wellness exam. Is the modifier necessary? When do we use it? Also, when do we use –PT, and how are these two modifiers different?

In fairness, this modifier was created in response to healthcare reform and, by necessity, came late in 2010. Additionally, the Centers for Medicare and Medicaid Services, the American Academy of Professional Coders, and the AMA continue to publish clarifications about the use of modifier 33, even though the code became applicable January 1.

To better understand this statement, let's define the key components.

Cost-sharing does not apply. This wording simply means that a patient's co-insurance, co-payment, and deductible are waived for the applicable services.

The Patient Protection and Affordable Care Act made it mandatory for all healthcare insurance plans to start to cover some preventive services and immunizations as part of all benefit plans. Specified preventive services are not subject to deductibles, co-insurance, and co-pays.

Modifier 33: preventive service. Modifier 33 is applied to indicate that the preventive service is one that waives a patient's co-pay, deductible, and co-insurance. An exception is that modifier 33 does not have to be appended to those services that are inherently preventive (for instance, screening mammography).

Most of the services to which the modifier applies are not new, so the list will not surprise you. According to the AMA, CPT modifier 33 is applicable for the identification of preventive services without cost-sharing in these four categories:

The specific preventive services for which cost-sharing does not apply for Medicare patients:

Now to the other parts of your question.