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Internal Medicine

Thomas D. Mackenzie, MD

Works at hospitals in Denver, CO · Colorado

Summary

Thomas D. Mackenzie, MD (Internal Medicine) is listed by Medicare at 1 hospital in Denver, CO. NPI 1821007741. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Thomas D. Mackenzie, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Internal MedicinePrimary specialty
YesAccepts Medicare assignment
37Years since medical school (graduated 1989)
Washington University School Of MedicineMedical school
MaleGender (as listed)
Denver Health and Hospital AuthorityGroup practice

Quick answers

Which hospitals does Thomas D. Mackenzie work at?
Medicare's official clinician data lists Thomas D. Mackenzie at 1 hospital: Denver Health & Hospital Authority. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Thomas D. Mackenzie see patients?
Medicare's clinician data lists 1 practice location in Denver, CO. Call before your visit to confirm the address.
What is Thomas D. Mackenzie's specialty?
Medicare lists Internal Medicine as the primary specialty.
Does Thomas D. Mackenzie accept Medicare assignment?
Yes. Medicare's clinician data says Thomas D. Mackenzie accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
What is the phone number for Thomas D. Mackenzie?
(303) 436-6000, as listed in official Medicare / NPI Registry data.
What is Thomas D. Mackenzie's NPI number?
1821007741. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Thomas D. Mackenzie works

Medicare's Facility Affiliation Data lists Thomas D. Mackenzie at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Thomas D. Mackenzie is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Thomas D. Mackenzie as a member of this group (CMS data updated 2026-10-02).

  • Denver Health and Hospital Authority849 clinicians in the group

Specialties

Find other Internal Medicine doctors in Colorado →

Other internal medicine doctors in Denver

Clinicians with the same Medicare primary specialty in Denver, CO — not a recommendation.

All internal medicine doctors in Denver →

Clinician information

CredentialMD
Medical schoolWashington University School Of Medicine
Graduation year1989
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1821007741
CorrectionsReport 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

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians