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CALVIN EVEREST WILLIAMS MD
NPI 1326085465
Anesthesiology in Saint Louis, MO

Active since May 31, 2006PECOS Enrolled
11133 DUNN RD, SAINT LOUIS, MO 63136(314) 653-5744 Get Directions Write a Review

NPPES record last updated: June 28, 2023. Verified against the NPPES registry weekly; last sync: November 01, 2026.

Record update history: Mar 7, 2023, Dec 8, 2021 (2 updates tracked since 2021).

About Calvin Everest Williams Md NPPES

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

CALVIN EVEREST WILLIAMS MD (NPI 1326085465) is an individual anesthesiology provider in Saint Louis, Missouri, licensed in Missouri (R3C29) and active in the NPI registry since May 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1326085465
Entity TypeIndividualMale
Primary Taxonomy207L00000X
Provider Legal NameCALVIN EVEREST WILLIAMSCredential: MD
Location Address11133 DUNN RDSaint Louis, MO 63136-6119
Mailing Address15282 Brightfield Manor DrChesterfield, MO 63017-2486 · (314) 941-6355
Phone(314) 653-5744
Sole ProprietorYes
Enumeration DateMay 31, 2006
Last NPPES UpdateJune 28, 20232 updates tracked since enumeration
NPPES CertifiedJune 28, 2023
✔ NPI 1326085465 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAnesthesiologyAllopathic & Osteopathic Physicians
Taxonomy Code207L00000X
Licenses✔ Licensed in MO · R3C29✔ Licensed in MO · MDR329
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.
11133 DUNN RD, Saint Louis, MO 63136
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Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Calvin Everest Williams Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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 Reassignment

Medicare enrollment records show Calvin Williams reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Midwest Anesthesia Providers S.C
Same address
Anesthesiology
11133 DUNN RD
Saint Louis, MO 63136
  • Reassigned Medicare billing, Illinois enrollment
  • Medicare enrollment name: Midwest Anesthesia Providers Sc
  • 253 clinicians in this Medicare group
NPI 1295189082 (865) 293-5676

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 3

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 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.
33 services32 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.
25 services24 patients
Anesthesia for x-ray or radiation therapy 01922
Anesthesia for x-ray or radiation therapy involves administering medication to help you relax or sleep during the procedure. It's used to ensure comfort, minimize movement, and reduce anxiety. The type of anesthesia used depends on the procedure and patient's health.
13 services13 patients

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.

ALEXANDER SEXTRO CAA
Anesthesiologist Assistant
11133 DUNN RD
SAINT LOUIS, MO 63136
St. Louis County (314) 653-5000
DR. HILTON I PRICE MD
Radiology (Diagnostic Radiology)
11133 DUNN RD, DEPT RADIOLOGY
SAINT LOUIS, MO 63136
St. Louis County (314) 362-7200
LESLEY ANN HANSON D.O.
Internal Medicine (Critical Care Medicine)
11133 DUNN RD
SAINT LOUIS, MO 63136
St. Louis County (314) 317-0600
MARY A. RUDLOFF M.D.
Pathology (Anatomic Pathology)
11133 DUNN RD, DEPT. OF PATHOLOGY
SAINT LOUIS, MO 63136
St. Louis County (314) 653-5630
ELYSHA M KACHEVAS
Nurse Practitioner (Family)
11133 DUNN RD, SUITE 2335
SAINT LOUIS, MO 63136
St. Louis County (314) 653-5007
DR. GRACE ELIZABETH MONTES MD
Emergency Medicine
11133 DUNN RD, DEPT EMERGENCY MED
SAINT LOUIS, MO 63136
St. Louis County (314) 362-9123
MS. CHRISTIE MARIE KEEN FNP
Nurse Practitioner
11133 DUNN RD, DEPT EMERGENCY MED
SAINT LOUIS, MO 63136
St. Louis County (314) 362-9123
CHRISTIAN HOSPITAL NORTHEAST
Psychiatric Unit
11133 DUNN RD
SAINT LOUIS, MO 63136
St. Louis County (314) 653-5582

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 Calvin Williams's NPI number?

The NPI number for Calvin Williams is 1326085465. It was assigned to this individual provider in the NPPES registry on May 31, 2006.

Where is Calvin Williams located?

Calvin Williams practices at 11133 Dunn Rd, Saint Louis, MO 63136. The listed phone number is (314) 653-5744.

What is Calvin Williams's specialty?

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

Is Calvin Williams enrolled in Medicare?

Yes. Calvin Williams is registered in the Medicare PECOS enrollment system.

Which organization bills Medicare for Calvin Williams's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Calvin Williams reassigns Medicare benefits to Midwest Anesthesia Providers S.C (Saint Louis, MO). The 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 Calvin Williams's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Calvin Williams was last updated on June 28, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.