1. NPM Knowledge Base
  2. Medical billing in dentistry

KX modifier

Explanation of KX modifier and it where to add it onto claim form


The modifier KX carries a lot of weight on a medical claim form, so it is important to be aware of what it means, as well as when it should, and should not be used.

The modifier KX stands for: Requirements specified in the medical policy have been met

Currently, dental practices who have enrolled as participating or non-participating Medicare DME suppliers can use this modifier to indicate the oral appliance for Obstructive Sleep Apnea (OSA) and the patient themselves that they are billing for has met all of the required coverage criteria. Also, there have been recent reports of certain commercial insurers starting to accept the KX modifier as well.

So in plain words: using the KX modifier mean you do not have to submit the supporting documentation with your claim, however it is important to be sure you have the information documented, because the insurer can request for it to be submitted at a later date! (or, may look for the information during an audit).

A fact sheet on modifier KX provided by WPS (a medicare contractor) states the following:

"Appropriate Usage: When additional documentation is available to support the medical necessary service under a medical policy

Inappropriate Usage: When the claim will be denied for statute, and/or when all information is represented on the claim, and the medical notes will not offer any further clarification"

Below is an example of the KX modifier on a Medicare DME claim:

The LCD's for oral appliances for OSA state:

"Suppliers must add a KX modifier to a code only if all of the criteria in the "Indications and Limitations of Coverage and/or Medical Necessity" section of this policy have been met. If the requirements for the KX modifier are not met, the KX modifier must not be used.

If all of the coverage criteria have not been met, the GA or GZ modifier must be added to a claim line for the oral appliance. When there is an expectation of a medical necessity denial, suppliers must enter the GA modifier on the claim line if they have obtained a properly executed Advance Beneficiary Notice (ABN) or the GZ modifier if they have not obtained a valid ABN. Claim lines billed without a GA, GZ, or KX modifier will be rejected as missing information."