1. Home
  2. Directory
  3. New York
  4. Smithtown
  5. Anesthesiology
  6. NPI Profile

DR. ALLEN M. WILLIAMS M.D.
NPI 1720062680
Anesthesiology in Smithtown, NY

Active since December 05, 2005PECOS EnrolledAccepts Medicare Assignment
415 W MAIN ST, SMITHTOWN, NY 11787(631) 521-7341(631) 521-7342 Get Directions Write a Review

NPPES record last updated: March 18, 2014. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. Allen M. Williams M.d. NPPES

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

DR. ALLEN M. WILLIAMS M.D. (NPI 1720062680) is an individual anesthesiology provider in Smithtown, New York, licensed in New York (223882) and active in the NPI registry since December 2005. He is enrolled in Medicare PECOS, is affiliated with John T Mather Memorial Hospital Of Port Jefferson, and is a graduate of Other (1991).

NPPES Registry Identity

NPI1720062680
Entity TypeIndividualMale
Primary Taxonomy207L00000X
Provider Legal NameDR. ALLEN M. WILLIAMSCredential: M.D.
Location Address415 W MAIN STSmithtown, NY 11787-2612
Mailing Address415 W Main StSmithtown, NY 11787-2612 · (631) 521-7341 · Fax (631) 521-7342
Phone(631) 521-7341
Fax(631) 521-7342
Sole ProprietorYes
Medical School CMSOtherGraduated 1991
Enumeration DateDecember 5, 2005
Last NPPES UpdateMarch 18, 2014
✔ NPI 1720062680 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAnesthesiologyAllopathic & Osteopathic Physicians
Taxonomy Code207L00000X
License✔ Licensed in NY · 223882
Definition
An anesthesiologist is trained to provide pain relief and maintenance, or restoration, of a stable condition during and immediately following an operation or an obstetric or diagnostic procedure. The anesthesiologist assesses the risk of the patient undergoing surgery and optimizes the patient's condition prior to, during and after surgery. In addition to these management responsibilities, the anesthesiologist provides medical management and consultation in pain management and critical care medicine. Anesthesiologists diagnose and treat acute, long-standing and cancer pain problems; diagnose and treat patients with critical illnesses or severe injuries; direct resuscitation in the care of patients with cardiac or respiratory emergencies, including the need for artificial ventilation; and supervise post-anesthesia recovery.
415 W MAIN ST, Smithtown, NY 11787
Open in Google Maps ↗

Other Identifiers 3

Medicare UPINH55163NY
Medicare PIN8K3381NY
Medicaid02246091NY

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Allen M. Williams 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 ID42204224
PECOS Enrollment IDI20040830000933
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.

Medicare Billing Reassignments

5

Medicare enrollment records show Allen Williams reassigns Medicare billing to 5 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Jamaica Anesthesiologist, PC
34 mi
Anesthesiology
8900 VAN WYCK EXPY
Jamaica, NY 11418
  • Reassigned Medicare billing, New York enrollment
  • 163 clinicians in this Medicare group
NPI 1508812892 (718) 206-6088
Montefiore Medical Center
35 mi
Anesthesiology
111 E 210TH ST
Bronx, NY 10467
  • Reassigned Medicare billing, New York enrollment
  • 5,251 clinicians in this Medicare group
NPI 1063525152 (914) 378-6021
Bronx Anesthesia Services, PC
36 mi
Anesthesiology
4422 3RD AVE
Bronx, NY 10457
  • Reassigned Medicare billing, New York enrollment
  • 72 clinicians in this Medicare group
NPI 1225330103 (877) 580-4635
North Shore - Lij Anesthesiology, PC
36 mi
Anesthesiology
480 BEDFORD RD BLDG B
Chappaqua, NY 10514
  • Reassigned Medicare billing, New York enrollment
  • 1,406 clinicians in this Medicare group
NPI 1417401266 (914) 666-8866
Oswego Hospital
247 mi
Anesthesiology
110 W 6TH ST
Oswego, NY 13126
  • Reassigned Medicare billing, New York enrollment
  • 122 clinicians in this Medicare group
NPI 1255639043 (315) 349-5511

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 6

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.

Anesthesia for lens surgery 00142
Anesthesia for lens surgery involves administering medication to numb the eye area, ensuring you feel no pain during the procedure. This can be a local anesthetic (numbing only the eye area) or general (where you're asleep). It helps make the surgery comfortable and stress-free.
23 services22 patients
Anesthesia for other procedure on esophagus, stomach, or upper small bowel using an endoscope 00731
This procedure involves the use of an endoscope, a flexible tube with a light and camera, to examine your esophagus, stomach, or upper small bowel. Anesthesia ensures you are comfortable and pain-free during the procedure.
21 services21 patients
Anesthesia for other procedure on esophagus, stomach, or upper small bowel using an endoscope 00731
This procedure involves the use of an endoscope, a flexible tube with a light and camera, to examine your esophagus, stomach, or upper small bowel. Anesthesia ensures you are comfortable and pain-free during the procedure.
19 services19 patients
Anesthesia for other procedure on large bowel using an endoscope 00811
Anesthesia for an endoscopic procedure on the large bowel ensures comfort and relaxation during the procedure. You'll be given medication to make you drowsy or asleep, eliminating any discomfort. The medication can be administered through a vein or inhaled.
19 services19 patients
Anesthesia for other procedure on large bowel using an endoscope 00811
Anesthesia for an endoscopic procedure on the large bowel ensures comfort and relaxation during the procedure. You'll be given medication to make you drowsy or asleep, eliminating any discomfort. The medication can be administered through a vein or inhaled.
16 services16 patients
Anesthesia for procedure on small and large bowel using an endoscope 00813
Anesthesia for an endoscopic procedure on the small and large bowel ensures comfort and relaxation during the procedure. It involves administering medicine to help you sleep or feel drowsy. This allows the doctor to examine your bowels without causing you discomfort or pain.
16 services16 patients

Hospital Affiliations CMS Care Compare

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

John T Mather Memorial Hospital Of Port Jefferson

Acute Care Hospitals · Port Jefferson, NY
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number330185
Location75 North Country RoadPort Jefferson, NY 11777 · Suffolk County
Emergency services

Other Providers at the Same Location NPPES

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

ALLEN MALCOLM WILLIAMS, M.D., PLLC
Anesthesiology
415 W MAIN ST
SMITHTOWN, NY 11787
Suffolk County (631) 521-7341

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 Allen Williams's NPI number?

The NPI number for Allen Williams is 1720062680. It was assigned to this individual provider in the NPPES registry on December 5, 2005.

Where is Allen Williams located?

Allen Williams practices at 415 W Main St, Smithtown, NY 11787. The listed phone number is (631) 521-7341.

What is Allen Williams's specialty?

The primary specialty registered for this NPI is Anesthesiology with taxonomy code 207L00000X.

Is Allen Williams enrolled in Medicare?

Yes. Allen Williams 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.

Which organizations bill Medicare for Allen Williams's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Allen Williams reassigns Medicare benefits to 5 organizations: Jamaica Anesthesiologist, PC (Jamaica, NY), Montefiore Medical Center (Bronx, NY), Bronx Anesthesia Services, PC (Bronx, NY), North Shore - Lij Anesthesiology, PC (Chappaqua, NY) and Oswego Hospital (Oswego, NY). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Allen Williams's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Allen Williams affiliated with any hospitals?

According to CMS data, Allen Williams is affiliated with John T Mather Memorial Hospital Of Port Jefferson.

When was this NPI record last updated?

The NPPES record for Allen Williams was last updated on March 18, 2014. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 years 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.