HAP Radiology Billing and Coding Blog

When & How to Bill For Locum Tenens Services In The Radiology Practice

Posted: By Sandy Coffta on March 22, 2022

When & How to Bill For Locum Tenens Services In The Radiology PracticeThe workload of a radiology practice doesn’t diminish when one of the physicians is away, either on leave or due to termination, and one way to cope with the shortfall of staff is to use a temporary physician service. Knowing how to properly bill for those services is essential to maintaining cash flow in compliance with the regulations.

What is a locum tenens?

The dictionary defines locum tenens as “one filling an office for a time or temporarily taking the place of another - used especially of a doctor or clergyman.” The key part of the phrase is temporarily taking the place of another. Medicare has officially adopted the term “Fee-For-Time Compensation Arrangement” in place of the term “Locum Tenens Arrangements.”

Under what circumstances can a practice bill for a locum tenens?

When a regular staff physician will be away temporarily, the practice might want to bring in a substitute physician in order to maintain their productivity. The absence could be due to illness, maternity leave, vacation, or continuing education.


A radiology group may also bill for a substitute physician when a radiologist has left the group, but a permanent replacement has not yet been hired.

View a recording of our webinar 2022 Updates to the MPFS & Radiology  Reimbursement Impact

Are there limitations or other restrictions?

The substitute physician arrangement cannot extend beyond sixty (60) continuous days of coverage for the regular physician. During the coverage period, the regular physician must not be available in the practice; in other words, the regular physician and the substitute may not both bill for services at the same time. If the regular physician returns to the practice and then leaves again, a new 60-day period would begin.


There is one exception to the 60-day limit. When a physician is absent because they were called to active duty in the Armed Forces, a substitute physician may exceed the 60-day limit.


For the purpose of substitute physician billing, a physician who has left the group practice is considered to be a part of the group practice for up to 60 days, thus allowing the practice to use a temporary substitute during that period. The 60-day period cannot be extended even if a different substitute physician is brought in.

How do we bill for the substitute physician?

The practice bills for the services of the substitute and then pays compensation from the practice in the form of a per diem or similar arrangement. The practice will enter modifier Q6 and the regular physician’s National Provider Identifier (NPI) as the Rendering Provider for each service provided by the substitute in Box 24 of the CMS-1500 form, or in the appropriate place when billing electronically. The substitute must have their own NPI number, which must be retained in the group’s records, although it is not required to be entered on the claim.


It is important to note that a substitute physician does not assign their benefits to the group practice using the form CMS-855R. The substitute physician does not bill Medicare for his or her services.

What happens if the regular staff physician is out for more than 60 days?

Once the initial 60-day period expires the substitute would have to be a credentialed member of the practice to continue. If it appears that the regular physician will be absent for more than 60 days, it would be wise to begin to credential the substitute as early as possible.

Can we bill a new physician as a substitute while waiting for them to be credentialed?

If a physician has been hired as a permanent member of the practice, then it would not be appropriate to bill them as a substitute. Ideally the credentialing of a new physician should begin at least 60 days before their start date, if possible. However, if the new physician is replacing a physician who has left the group, then they can be billed as a substitute physician for the first 60 days under the rules described above. In this case it would be best to pay the incoming physician as an independent contractor rather than as an employee in order to assure that the arrangement is compliant with CMS regulations.

What other rules are there?

The fee-for-time compensation rules apply only when one physician replaces another physician. Accordingly, they do not apply to non-physician providers such as nurse practitioners, physician assistants or radiology assistants.


The agreement with the substitute physician should be in writing. This provides documentation in support of the arrangement in the event of a Medicare audit, and it also serves to avoid any misunderstanding between the practice and the substitute physician.

Do the same rules apply to commercial payers?

Not necessarily. Although many commercial payers recognize substitute physicians in the same way Medicare does, the best practice for the group would be to check with their contracted payers. Some require an abbreviated credentialing process before modifier Q6 will be recognized.


If there is any chance that the substitute will exceed the 60-day threshold, credentialing with the most important payers should begin as early as possible.

What is the best source of information on billing for a substitute physician?

The Medicare claims processing manual Section 10.2.11 describes in detail all the rules we have summarized here.

Contact HAP


Our blog is designed to keep our readers informed about proper revenue cycle management and up to date with the latest changes. Subscribe today to be sure your practice reimbursement is at its best.


Sandy Coffta is the Vice President of Client Services at Healthcare Administrative Partners.


Related Articles

Legal Win Forces a Change to the No Surprises Act


Strengthening Congressional Support Addresses Medicare Physician Fee Schedule Interventional Radiology Cuts


Coverage is Expanded for Lung Cancer Screening Using LDCT



Inside advice from radiology RCM experts



Follow HAP on LinkedIn

Follow HAP on Twitter
Like HAP on Facebook


Copyright © 2022 Healthcare Administrative Partners. All Rights Reserved. 

Topics: radiology billing, radiology, locum tenens

Subscribe to our radiology billing and coding blog

Recent Posts


How a radiology practice recovered lost referrals