Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
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Leah Ayn Mergen, PA-C

Individual provider Physician Assistant · NPI 1023389392

Leah Ayn Mergen, PA-C is a Physician Assistant in Sioux Falls, South Dakota. Qualified in 2011, 15 years ago. Practices with Avera McKennan, a 962-clinician group and accepts Medicare assignment. Licensed in South Dakota.

Years since qualifying
15
Licensed in
SD
In the registry since
2012
What do these letters mean?
PA-C — Physician Assistant, Certified
A physician assistant who holds current national certification.

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Practice location Address checks out

521 N Main Ave Ste 100
Sioux Falls, SD 57104-5947
Phone: (605) 367-8214
Show map & directions

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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Physician Assistant (primary) Taxonomy 363A00000X · Licence 0799 (SD)

Record details

NPI number1023389392
Entity typeIndividual (Type 1)
GenderFemale
Credentials PA-C
Sole proprietorNo
NPI enumeratedJanuary 19, 2012
Last updated in NPPESAugust 29, 2017

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyPHYSICIAN ASSISTANT
Medical schoolOTHER
Graduated 2011 (15 years in practice)
Group practice Avera McKennan — 962 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations3 on file with Medicare

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients131
Services billed 258 a service is one billed item, such as a visit, a test or a procedure
Average patient age70

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Payments from drug and device companies, 2025

Drug and device makers are required by federal law (the Physician Payments Sunshine Act) to report what they pay or give to clinicians, and CMS publishes the reports as Open Payments. This is the 2025 program year. A report is a record of a payment, not an allegation of anything, and many are small items such as meals. Only general payments are listed here; research payments and ownership or investment interests are reported separately by CMS and are not shown.

Food and Beverage $55 2 payments · a meal or drink at a meeting or visit, not a fee

Each amount is the sum of what companies reported for that kind of payment in 2025, rounded to the dollar. Not all of it is income to the clinician: a meal is not a fee, a charitable contribution goes to a charity, and a royalty or an acquisition payment is not a salary.

Check a report, or dispute one, at the source in CMS’s own tool, Open Payments. Corrections go through CMS’s dispute process. This site removes a home address on request and asks for no proof, because that is privacy; it will not remove an accurate payment report on request, because that is a statutory public disclosure.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician. Those with a page here are linked.

  • Avera @ Home Home health agency · Sioux Falls, SD · listed as Avera at Home
  • Avera McKennan Hospital & University Health Center Hospital · Sioux Falls, SD

Colleagues at Avera McKennan

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 962 clinicians in the practice; 12 are shown here.

Other providers in Sioux Falls