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Psychiatry

Theunis O. De Boer, MD

Sees patients in Derry, NH · New Hampshire

Summary

Dr. Theunis O. De Boer, MD is a psychiatrist at 10 Tsienneto Rd, Derry, NH 03038. Phone: (603) 434-1577. Accepts Medicare assignment. NPI 1558001354. Source: CMS National Downloadable File, updated October 2, 2026.

  • Specialty: Psychiatrist (Medicare lists Psychiatry)
  • Address: 10 Tsienneto Rd, Derry, NH 03038 · Directions
  • Phone: (603) 434‑1577
  • Medicare: Accepts Medicare assignment
  • Group practice: Mental Health Center for Southern New Hampshire Inc
  • Medical school: Northeastern Ohio University College Of Medicine · graduated 2022 (4 years since medical school)
  • Gender (as listed): Male
  • Telehealth: offered

From official Medicare data

This page shows what Medicare's official clinician data says about Theunis O. De Boer, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Theunis O. De Boer accept Medicare assignment?
Yes. Medicare's clinician data says Theunis O. De Boer 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.
What is Theunis O. De Boer's NPI number?
1558001354. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Theunis O. De Boer is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Theunis O. De Boer as a member of this group (CMS data updated October 2, 2026).

  • Mental Health Center for Southern New Hampshire Inc15 clinicians in the group

Specialties

Find other Psychiatry doctors in New Hampshire →

Other psychiatrists in Derry

Clinicians with the same Medicare primary specialty in Derry, NH — not a recommendation.

All psychiatrists in Derry →

Other clinicians in Mental Health Center for Southern New Hampshire Inc

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolNortheastern Ohio University College Of Medicine
Graduation year2022 (4 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1558001354
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians