THOMAS G MASON II M.D.
NPI 1104805522
Internal Medicine - Rheumatology in Rochester, MN

Active since January 13, 2006PECOS EnrolledAccepts Medicare Assignment
200 1ST ST SW, ROCHESTER, MN 55905(507) 284-2511 Get Directions Write a Review

NPPES record last updated: September 5, 2025. Verified against the NPPES registry weekly; last sync: August 16, 2026.

Record update history: Sep 5, 2025, May 16, 2025, Aug 18, 2020 and 2 more (5 updates tracked since 2018).

About Thomas G Mason Ii M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

THOMAS G MASON II M.D. (NPI 1104805522) is an individual rheumatology provider in Rochester, Minnesota, licensed in Minnesota (36621) and active in the NPI registry since January 2006. He is enrolled in Medicare PECOS, is affiliated with Mayo Clinic Hospital Rochester, and is a graduate of West Virginia University School Of Medicine (1986).

NPPES Registry Identity

NPI1104805522
Entity TypeIndividualMale
Primary Taxonomy207RR0500X
Provider Legal NameTHOMAS G MASON IICredential: M.D.
Location Address200 1ST ST SWRochester, MN 55905-0001
Mailing AddressPo Box 860912Minneapolis, MN 55486-0912 · (507) 284-2511
Sole ProprietorNo
Medical School CMSWest Virginia University School Of MedicineGraduated 1986
Enumeration DateJanuary 13, 2006
Last NPPES UpdateSeptember 5, 20255 updates tracked since enumeration
NPPES CertifiedSeptember 5, 2025
NPI 1104805522 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

Primary SpecialtyInternal Medicine · RheumatologyAllopathic & Osteopathic Physicians
Taxonomy Code207RR0500X
License Licensed in MN · 36621
Definition
An internist who treats diseases of joints, muscle, bones and tendons. This specialist diagnoses and treats arthritis, back pain, muscle strains, common athletic injuries and collagen diseases.
200 1ST ST SW, Rochester, MN 55905

Accepted Insurance

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

Enrolled in Medicare and accepts Medicare assignment

Thomas G Mason Ii M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID648312280
PECOS Enrollment IDI20100120000888
Eligible to Order & Refer Part B Labs & Imaging Durable Medical Equipment Home Health Agency Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims 6

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Injection, triamcinolone acetonide, not otherwise specified, 10 mg J3301
Triamcinolone acetonide is a medication used to reduce inflammation in the body. It's given as a 10 mg injection for conditions like allergies, arthritis, or skin problems. The injection helps to decrease swelling, redness, and itching.
224 services20 patients
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
48 services39 patients
New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203
This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.
44 services44 patients
Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214
This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.
37 services31 patients
Aspiration and/or injection of fluid large joint using ultrasound guidance 20611
This procedure involves using ultrasound technology to accurately locate a large joint, usually the knee or shoulder. A needle is then inserted to either extract fluid (aspiration) or inject medication. The ultrasound helps ensure precision and safety.
35 services32 patients
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204
This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.
22 services22 patients

Hospital Affiliations CMS Care Compare

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Mayo Clinic Hospital Rochester

Acute Care Hospitals · Rochester, MN
5/5 CMS rating
OwnershipVoluntary non-profit - Church
CMS Certification Number240010
Location1216 Second Street SouthwestRochester, MN 55902 · Olmsted County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 55905 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$127.61 typical visit price
range $56.00 – $168.28
Typical copayment $31.90 (range $14.00 – $42.07)
Most-billed visit code 99204
Established Patient
$98.61 typical visit price
range $18.32 – $138.04
Typical copayment $24.65 (range $4.58 – $34.51)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

Internal Medicine
200 1ST ST SW
ROCHESTER, MN 55905
Pathology (Clinical Pathology/Laboratory Medicine)
200 1ST ST SW
ROCHESTER, MN 55905
Nurse Practitioner
200 1ST ST SW
ROCHESTER, MN 55905
Nurse Practitioner
200 1ST ST SW
ROCHESTER, MN 55905
Optometrist
200 1ST ST SW
ROCHESTER, MN 55905
Psychologist
200 1ST ST SW
ROCHESTER, MN 55905
Nurse Anesthetist, Certified Registered
200 1ST ST SW
ROCHESTER, MN 55905
Internal Medicine (Endocrinology, Diabetes & Metabolism)
200 1ST ST SW
ROCHESTER, MN 55905

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Thomas Mason's NPI number?

The NPI number for Thomas Mason is 1104805522. It was assigned to this individual provider in the NPPES registry on January 13, 2006.

Where is Thomas Mason located?

Thomas Mason practices at 200 1st St SW, Rochester, MN 55905. The listed phone number is (507) 284-2511.

What is Thomas Mason's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Rheumatology, with taxonomy code 207RR0500X.

Is Thomas Mason enrolled in Medicare?

Yes. Thomas Mason is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Thomas Mason accept?

Health plans from Medica list Thomas Mason as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Thomas Mason affiliated with any hospitals?

According to CMS data, Thomas Mason is affiliated with Mayo Clinic Hospital Rochester.

When was this NPI record last updated?

The NPPES record for Thomas Mason was last updated on September 5, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.