Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

JONATHAN GAMSS M.D.
NPI 1598922874
Internal Medicine in Mount Kisco, NY

Active since May 22, 2008PECOS EnrolledAccepts Medicare Assignment
400 E MAIN ST, NORTHERN WESTCHESTER HOSPITAL, MOUNT KISCO, NY 10549(914) 666-1680(914) 666-1965 Get Directions Write a Review

NPPES record last updated: June 11, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

Record update history: Nov 18, 2024, Nov 20, 2020 (2 updates tracked since 2020).

About Jonathan Gamss M.d. NPPES

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

JONATHAN GAMSS M.D. (NPI 1598922874) is an individual internal medicine provider in Mount Kisco, New York, licensed in New York (246486) and active in the NPI registry since May 2008. He is enrolled in Medicare PECOS, is affiliated with Clara Maass Medical Center, and maintains 4 additional practice locations.

NPPES Registry Identity

NPI1598922874
Entity TypeIndividualMale
Primary Taxonomy207R00000X
Provider Legal NameJONATHAN GAMSSCredential: M.D.
Location Address400 E MAIN ST, NORTHERN WESTCHESTER HOSPITALMount Kisco, NY 10549-3417
Mailing Address400 E Main St, Northern Westchester Hospital, Medical Affairs OfficeMount Kisco, NY 10549-3417 · (914) 666-1680 · Fax (914) 666-1965
Fax(914) 666-1965
Sole ProprietorNo
Medical School CMSOtherGraduated 2004
Enumeration DateMay 22, 2008
Last NPPES UpdateJune 11, 20262 updates tracked since enumeration
NPPES CertifiedJune 11, 2026
NPI 1598922874 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
Licenses Licensed in NY · 246486 Licensed in FL · ME178297 Licensed in CO · DR.0076561
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
Also ListedEmergency MedicineTaxonomy 207P00000X · License 25MA08623200 (NJ)
400 E MAIN ST, Mount Kisco, NY 10549

Secondary Practice Locations 4

Location 115310 Amberly Dr # 66Tampa Palms, FL 33647-2199 · Phone (718) 819-6144 · Fax (718) 819-6145
Location 210465 Melody Dr Ste 123Northglenn, CO 80234-4101 · Phone (718) 819-6144 · Fax (718) 819-6145
Location 33611 14th Ave Ste 550Brooklyn, NY 11218-3773 · Phone (718) 819-6144 · Fax (718) 819-6145
Location 4391 E 149th St Ste 403Bronx, NY 10455-3907 · Phone (718) 819-6144 · Fax (718) 819-6145

Other Identifiers 1

Medicaid03040282NY

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

Jonathan Gamss 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 ID345311015
PECOS Enrollment IDI20080624000502, I20100325000556
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 8

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.

Emergency department visit with high level of medical decision making 99285
An emergency department visit for severe conditions is when you urgently seek medical help due to serious health issues. These could be severe injuries, breathing problems, unbearable pain, or sudden severe illness. Doctors and nurses will provide immediate care to stabilize your condition.
430 services401 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.
78 services61 patients
Emergency department visit with moderate level of medical decision making 99284
An emergency department visit for a high-severity issue means you're experiencing a serious health problem that needs immediate attention. This could be a severe injury, serious illness, or life-threatening condition. Medical professionals will provide urgent care to stabilize your condition.
71 services66 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.
58 services52 patients
Critical care, first 30-74 minutes 99291
Critical care involves immediate and constant attention by a team of specially-trained health professionals. It's for patients with life-threatening conditions, requiring first 30-74 minutes of intense monitoring and treatment.
33 services32 patients
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223
Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.
28 services26 patients

Hospital Affiliations CMS Care Compare

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

Clara Maass Medical Center

Acute Care Hospitals · Belleville, NJ
1/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number310009
LocationOne Clara Maass DriveBelleville, NJ 07109 · Essex County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 10549 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
$154.28 typical visit price
range $67.40 – $203.53
Typical copayment $38.57 (range $16.85 – $50.88)
Most-billed visit code 99204
Established Patient
$117.62 typical visit price
range $21.66 – $164.45
Typical copayment $29.40 (range $5.41 – $41.11)
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.

Anesthesiology
400 E MAIN ST, NORTHERN WESTCHESTER HOSPITAL
MOUNT KISCO, NY 10549
Emergency Medicine
400 E MAIN ST
MOUNT KISCO, NY 10549
Anesthesiology (Critical Care Medicine)
400 E MAIN ST
MOUNT KISCO, NY 10549
Student in an Organized Health Care Education/Training Program
400 E MAIN ST
MOUNT KISCO, NY 10549
Pediatrics (Neonatal-Perinatal Medicine)
400 E MAIN ST, NORTHERN WESTCHESTER HOSPITAL
MOUNT KISCO, NY 10549
Internal Medicine
400 E MAIN ST, NORTHERN WESTCHESTER HOSPITAL
MOUNT KISCO, NY 10549
Student in an Organized Health Care Education/Training Program
400 E MAIN ST
MOUNT KISCO, NY 10549
Surgery
400 E MAIN ST, NWH NORTH BUILDING 1ST FLOOR
MOUNT KISCO, NY 10549

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 Jonathan Gamss's NPI number?

The NPI number for Jonathan Gamss is 1598922874. It was assigned to this individual provider in the NPPES registry on May 22, 2008.

Where is Jonathan Gamss located?

Jonathan Gamss practices at 400 E Main St Northern Westchester Hospital, Mount Kisco, NY 10549. The listed phone number is (914) 666-1680.

What is Jonathan Gamss's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Jonathan Gamss enrolled in Medicare?

Yes. Jonathan Gamss 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.

Is Jonathan Gamss affiliated with any hospitals?

According to CMS data, Jonathan Gamss is affiliated with Clara Maass Medical Center.

When was this NPI record last updated?

The NPPES record for Jonathan Gamss was last updated on June 11, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 57 days 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.