NPPES file of Aug 9, 2026

Thorvardur R. Halfdanarson, M.D.

Medical Oncology Physician · Rochester, MN

Thorvardur R. Halfdanarson, M.D. is a medical oncology physician with a practice address in Rochester, Minnesota, and NPI 1083684187, issued on Jan 23, 2006. Check the license (Minnesota 45995, as entered in NPPES) on the Minnesota Board of Medical Practice; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1083684187
Name
Thorvardur R. Halfdanarson
Credential
M.D.
Primary taxonomy
Medical Oncology Physician 207RX0202X
License numbers
45995 MN
46666 AZ
37199 IA
Self-reported in NPPES; status is on the state search
Practice location
200 1St St SW, Rochester, MN 55905
Phone
(507) 284-2511
Enumerated
Jan 23, 2006
Record last updated
Aug 14, 2020 (not updated in 6 years: call before relying on the address or phone)
Medicare enrollment
Enrolled (PECOS I20031217000216); accepts Medicare assignment
Telehealth
Offers telehealth (CMS)
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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8 nearest medical oncology physician records → All 159 in Minnesota → Look up another NPI →

Also registered at 200 1St St SW

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Timothy Aadland, M.D.Diagnostic Radiology Physician1780662783
  2. Christopher Aakre, MDInternal Medicine Physician1508151663
  3. Kathryn Aaro, P.T.Physical Therapist1619360666
  4. Danielle Aase, MDReproductive Endocrinology Physician1316524135
  5. Uzoamaka Abajue, PHARMDPharmacist1982335295
  6. Francisco Abarca Rendon, MDIndependent Medical Examiner Physician1790096246

Verify Thorvardur R. Halfdanarson in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMinnesota Board of Medical Practice
    Search for license 45995    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the Minnesota license search

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78% fewer Medicare Part D claims than the average medical oncology physician in 2024

153 Medicare Part D claims for 55 beneficiaries, against an average of 703 among the 4,230 providers of this specialty who prescribed in Part D. Brand-name drugs were 35% of claims.

  1. Thorvardur Halfdanarson153
  2. Specialty average703

Most prescribed

  1. Colestipol Hcl24 claims
  2. Xermelo16 claims
  3. Eliquis15 claims
  4. Ondansetron Hcl14 claims

Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.

Industry payments in 2024: $17,811.98

19 payments; by number, the most common kind was food and beverage; the largest payer was Exelixis Inc. The 3,343 providers of this specialty with any payment received $11,773.47 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Thorvardur Halfdanarson$17,812
  2. Specialty average$11,773

Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.

Bills Medicare through one group practice

  1. Mayo ClinicRochester, MN

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

Thorvardur R. Halfdanarson among 159 medical oncology physician records in Minnesota

Thorvardur R. Halfdanarson, M.D. is one of 159 medical oncology physician records with a practice address in Minnesota. 82% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 13% of them.

  • NPI issued2006 · 13% of these records are older, 48% newer
  • In a Medicare fileYes · 82% of these records are
  • In the CMS Doctors and Clinicians fileYes · 75% of these records are
  • Graduated1995 · median 2004 among the 119 with a school on file
  • Record last updated2020 · 47% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RX0202X and a Minnesota practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Medical Oncology Physician providers in Minnesota

There are 159 medical oncology physician records in Minnesota.

All 159 in Minnesota → Every provider in Rochester → Medical Oncology Physician nationwide →

The 8 medical oncology physician records with the nearest ZIP codes

  1. Alex Adjei, MD PHDRochester, MN 559051982680583
  2. Steven Alberts, M.D.Rochester, MN 559051780660209
  3. Jan Buckner, M.D.Rochester, MN 559051235115262
  4. Gary Croghan, M.D.Rochester, MN 559051407832421
  5. Stacy D'Andre, M.D.Rochester, MN 559051629053939
  6. Paul Haluska, M.D.Rochester, MN 559051790761450
  7. James Ingle, M.D.Rochester, MN 559051356327670
  8. Aminah Jatoi, M.D.Rochester, MN 559051437136553

Common questions

What is Thorvardur R. Halfdanarson, M.D.'s NPI number?

Thorvardur R. Halfdanarson, M.D.'s National Provider Identifier (NPI) is 1083684187, issued on Jan 23, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Thorvardur R. Halfdanarson, M.D. located?

The NPPES record lists a practice address at 200 1St St SW, Rochester, MN, 55905. Phone: (507) 284-2511. Providers update this record themselves, so call before visiting.

How can I verify Thorvardur R. Halfdanarson, M.D.'s license?

NPPES lists Minnesota license number 45995, as entered by the provider. Search the Minnesota Board of Medical Practice at https://mn.gov/boards/medical-practice/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Thorvardur R. Halfdanarson, M.D. prescribe under Medicare Part D?

In 2024, Thorvardur R. Halfdanarson, M.D. had 153 Medicare Part D claims for 55 beneficiaries; the average among medical oncology physician prescribers was 703. Part D covers Medicare prescriptions only.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.