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Edit this profileAt a glance
- 389 Whitney Ave, Whitney Office Suites #2, New Haven, CT 06511
About Dr. Gwilliam
Nathan R. Gwilliam, MD is a healthcare provider in New Haven, CT specializing in psychiatry. Nathan trained at Baylor College of Medicine, graduating in 2012. According to Medicare claims data, the services billed most often include established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more. This provider record is associated with NPI 1366882409.
Factual summary compiled by Guide.md from public records; not written by this provider.
Education & Training
Specialty
Credentials & Licensing
Medicare information
Exactly as CMS reports it (National Downloadable File, Opt-Out Affidavits, Order & Referring). Not an insurance directory; confirm coverage with the office.
Contact Information
- (203) 293-6258
- Email not available
Practice Locations
389 WHITNEY AVE WHITNEY OFFICE SUITES #2
New Haven, CT 06511
Conditions Commonly Evaluated or Treated
Within Psychiatry generally. Availability varies by clinician, training and location — this profile has not been claimed, so nothing here is a personal claim by the provider.
Conditions
Cognitive and adjustment
Eating, sleep, and somatic
Geriatric care
Mental Health
Neurodevelopmental and behavioral
Most searched conditions
Anxiety, trauma, and obsessive-compulsive
Mood disorders
Psychotic disorders
Substance-related and addictive
Addiction & Substance Use
Eating Disorders
Mood & Depression
Personality and dissociative
Sleep & Wakefulness
Procedures & services
Advanced treatment
Assessment
Most searched procedures
- Anxiety and depression treatment
- Cognitive behavioral therapy
- Medication management
- Psychiatric evaluation
- Telepsychiatry
Addiction care
Addiction Medicine
Assessments
Brain stimulation
Consultations
Diagnostics
Inpatient care
Interventional psychiatry
Psychotherapy
Sleep Medicine
Specialized care
Therapy
Therapy and care
Procedures Most Often Billed to Medicare
21 services · 14 patients · 1 distinct code
| Procedure | Type | Code | Services | Compared with peers |
|---|---|---|---|---|
| Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more | Office visit | 99215 |
21 | Less often than most peers in Psychiatry |
Source: CMS Medicare public data. Shows how often procedures were billed — not quality of care or patient satisfaction.
Related providers
Connections drawn from the registry and from what providers have told us. A link here is not a referral or an endorsement.
Other psychiatrists at this location 1
Same specialty, same street address — most likely the same department or group.
Related specialists at this location 8
Clinically related specialties at the same address — the people this provider most likely works alongside.
Also at this address 3
Providers at the same street address. Each files their own registry entry, so a shared practice often appears under several different names.
More connections — 24 related providers in 3 groups
Other psychiatrists in New Haven 8
Same specialty, same city.
Trained at Baylor College of Medicine 8
Other providers in the same specialty who trained at the same institution.
Class of 2012 at Baylor College of Medicine 8
Providers who graduated from the same medical school in the same year.
Common questions
What kind of doctor is Dr. Gwilliam?
Dr. Gwilliam is a psychiatrist in New Haven, CT. That is the designation recorded for this NPI in the federal registry, where it is listed as “Psychiatry”.
NPI registry
What is Dr. Gwilliam's address?
Dr. Gwilliam is listed at 389 Whitney Ave Whitney Office Suites #2, New Haven, CT 06511. Addresses come from the NPI registry and can lag a move, so confirm before travelling.
NPI registry
How can I make an appointment with Dr. Gwilliam?
The number on file is (203) 293-6258. Contact the office directly to confirm availability and scheduling.
NPI registry
What is the NPI for Dr. Gwilliam?
Dr. Gwilliam's National Provider Identifier is 1366882409. It is issued by the Centers for Medicare & Medicaid Services and is unique and permanent — it does not change if they move practice.
NPI registry
Where did Dr. Gwilliam train?
Dr. Gwilliam attended Baylor College of Medicine, graduating in 2012. This comes from the CMS National Downloadable File.
CMS public data
How much experience does Dr. Gwilliam have?
Dr. Gwilliam has 14 years experience. Calculated from a graduation year of 2012, reported in the CMS National Downloadable File.
CMS public data
What procedures does Dr. Gwilliam perform?
According to Medicare billing data, Dr. Gwilliam the Medicare record under this individual NPI shows mainly office visits and diagnostic testing. Hospital-based physicians usually have their procedural work billed by the facility rather than under their own number, so this is a floor on their practice, not a description of it. This reflects Medicare patients only and is billing volume, not a measure of quality.
Medicare claims
Is Dr. Gwilliam's profile verified?
Not yet. This profile is built from public federal data and has not been confirmed by Dr. Gwilliam. If this is you, claiming it is free.
Guide.md
Guide.md listings do not constitute medical advice or an endorsement.