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MARY LIZZIE THOMAS MD, MPH
NPI 1215556253
Internal Medicine in New Haven, CT

Active since April 09, 2020PECOS EnrolledAccepts Medicare Assignment
20 YORK ST, NEW HAVEN, CT 06510(203) 688-4242 Get Directions Write a Review

NPPES record last updated: April 30, 2025. Verified against the NPPES registry weekly; last sync: October 04, 2026.

Record update history: May 29, 2023, Apr 9, 2020 (2 updates tracked since 2020).

About Mary Lizzie Thomas Md, Mph NPPES

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

MARY LIZZIE THOMAS MD, MPH (NPI 1215556253) is an individual internal medicine provider in New Haven, Connecticut, licensed in Tennessee (73730) and active in the NPI registry since April 2020. She is enrolled in Medicare PECOS, is affiliated with Regional One Health, and maintains 2 additional practice locations.

NPPES Registry Identity

NPI1215556253
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameMARY LIZZIE THOMASCredential: MD, MPH
Location Address20 YORK STNew Haven, CT 06510-3220
Mailing AddressPo Box 208028New Haven, CT 06520-8028 · (203) 737-8866
Phone(203) 688-4242
Sole ProprietorYes
Medical School CMSIndiana University School Of MedicineGraduated 2020
Enumeration DateApril 9, 2020
Last NPPES UpdateApril 30, 20252 updates tracked since enumeration
NPPES CertifiedApril 23, 2025
✔ NPI 1215556253 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 4

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in TN · 73730
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 ListedInternal Medicine · Geriatric MedicineTaxonomy 207RG0300X · License 73730 (TN)
Also ListedInternal Medicine · Hospice and Palliative MedicineTaxonomy 207RH0002X · License 73730 (TN)
Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X
20 YORK ST, New Haven, CT 06510
Open in Google Maps ↗

Secondary Practice Locations 2

Location 1877 Jefferson AveMemphis, TN 38103-2807 · Phone (901) 545-7100
Location 2920 Madison Ave Ste 447Memphis, TN 38103-3438 · Phone (901) 448-5814

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Oscar Insurance Company.Insurance ›

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

Mary Lizzie Thomas Md, Mph 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 ID6608297635
PECOS Enrollment IDI20250613000375
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.

Hospital Affiliations CMS Care Compare

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

Regional One Health

Acute Care Hospitals · Memphis, TN
1/5 CMS rating
OwnershipGovernment - Hospital District or Authority
CMS Certification Number440152
Location877 Jefferson AvenueMemphis, TN 38103 · Shelby County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 06510 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
$138.84 typical visit price
range $60.82 – $183.10
Typical copayment $34.71 (range $15.20 – $45.77)
Most-billed visit code 99204
Established Patient
$106.68 typical visit price
range $19.76 – $149.26
Typical copayment $26.67 (range $4.94 – $37.31)
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.

AUDREY P SENIOR APRN
Nurse Practitioner (Family)
20 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-5860
DR. YEISID F FIGUEREDO M.D.
Pediatrics (Neonatal-Perinatal Medicine)
20 YORK ST, DEPT OF NEONATOLOGY
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-2320
YALE NEW HAVEN HOSPITAL
Durable Medical Equipment & Medical Supplies (Customized Equipment)
20 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-2046
TAYLOR KINGSTON
Dietitian, Registered
20 YORK ST, FOOD AND NUTRITION EPB806
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-9185
DR. TRAVIS DANIEL BONTRAGER MD
Hospitalist
20 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-1734
TERESA JOSEPH D.O.
Internal Medicine (Nephrology)
20 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 737-8894
MR. BRAD ST. MARTIN MD
Obstetrics & Gynecology
20 YORK ST
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 688-4242
BERNADETTE BIMONTE-HACKETT LCSW
Social Worker (Clinical)
20 YORK ST, SOCIAL WORK EP10-635
NEW HAVEN, CT 06510
South Central Connecticut Planning Region (203) 785-5161

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 Mary Thomas's NPI number?

The NPI number for Mary Thomas is 1215556253. It was assigned to this individual provider in the NPPES registry on April 9, 2020.

Where is Mary Thomas located?

Mary Thomas practices at 20 York St, New Haven, CT 06510. The listed phone number is (203) 688-4242.

What is Mary Thomas's specialty?

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

Is Mary Thomas enrolled in Medicare?

Yes. Mary Thomas 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.

What insurance does Mary Thomas accept?

Health plans from Oscar Insurance Company list Mary Thomas as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Mary Thomas affiliated with any hospitals?

According to CMS data, Mary Thomas is affiliated with Regional One Health.

When was this NPI record last updated?

The NPPES record for Mary Thomas was last updated on April 30, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 17 months 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.