Quick answers
- Does Tricia L. Merrigan accept Medicare assignment?
- Yes. Medicare's clinician data says Tricia L. Merrigan accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Tricia L. Merrigan see?
- In 2024, CMS data shows 278 Original Medicare patients and 496 services for Tricia L. Merrigan. This counts Original Medicare only and measures volume, not quality.
- What is Tricia L. Merrigan's NPI number?
- 1467548727. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Tricia L. Merrigan, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 278 |
|---|---|
| Services billed to Medicare | 496 |
| Different services or procedures | 32 |
| Participating Medicare provider | Yes |
| Average age of these patients | 73 |
Most frequent services
- Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more (99213)171 services
- Biopsy or removal of deep lymph nodes of underarm (38525)54 services
- Imaging of lymph nodes during surgery (38900)51 services
- New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more (99205)50 services
- Partial removal of breast (19301)48 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)75%
- High blood pressure65%
- High cholesterol65%
- Arthritis38%
- Osteoporosis28%
- Anxiety22%
Hospitals where Tricia L. Merrigan works
Medicare's Facility Affiliation Data lists Tricia L. Merrigan at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Avera Marshall Regional Medical CenterMarshall, MN · Critical Access Hospital · Emergency services: listed by Medicare · CCN 241359
- Avera McKennan Hospital & University Health CenterSioux Falls, SD · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 430016
- Avera St LukesAberdeen, SD · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 430014
- Lakes Regional HealthcareSpirit Lake, IA · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: listed by Medicare · CCN 160124
- Spencer Municipal HospitalSpencer, IA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 160112
Practice locations
Addresses where Tricia L. Merrigan is enrolled with Medicare (CMS data updated October 2, 2026).
- 1000 E 23rd StSioux Falls, SD 57105
- 1001 E 21st St, Suite 401Sioux Falls, SD 57105 (605) 322‑8920
- 1325 S Cliff AveSioux Falls, SD 57105
- 1325 S Cliff Ave, RadiologySioux Falls, SD 57105 (605) 322‑4878
- 300 22nd AveBrookings, SD 57006
Group practices
Medicare enrollment lists Tricia L. Merrigan as a member of this group (CMS data updated October 2, 2026).
- Avera McKennan959 clinicians in the group
Specialties
- General Surgeryprimary
Other general surgeons in Sioux Falls
Clinicians with the same Medicare primary specialty in Sioux Falls, SD — not a recommendation.
Other clinicians in Avera McKennan
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Sanford School Of Medicine Of University Of South Dakota |
| Graduation year | 2006 (20 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1467548727 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians