FAQs

The AQ modifier is used when the address of the location the services were rendered has a HPSA geographic designation but the zip code is not allowed for automatic payment. Eligibility is determined by designation as of Dec 31 of the prior year. For example: If your address became designated within 2018, you would append the AQ modifier on claims with DOS in 2019.

Additional information is located at Health Professional Shortage Area (HPSA).

Reviewed: 10/05/22

Use modifier 50 when bilateral surgeries are performed on both sides of the body during the same operative session or on the same day. Correct bilateral surgery billing will ensure timely and accurate processing of these claims.

View modifier usage for additional information related to the use of modifier 50.

Reviewed: 10/05/22

It is recommended that modifier 51 is not included on Medicare claims. National Government Services claims processing system has hard-coded logic to add the modifier 51 to the correct procedure code if necessary.

View modifier 51 for additional information related to the use of modifier 51.

Reviewed: 10/05/22

Use modifier QW with lab codes whose test has been granted waived status under CLIA requirements. If the modifier is appended to a lab code whose test is not waived, the claim will deny as unprocessable.

View CMS Categorization of Tests for additional information and a listing of waived tests.

Reviewed: 10/05/22

Modifier 99 should only be used if a single line item requires five or more modifiers. Submitting the 99 modifier along with other modifiers will cause claim denials, delay in processing/payment of your claims and improper payment.

Visit Appropriate Usage of Modifier 99 for additional information.

Reviewed: 10/05/22