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WILLIAM R GRIER M.D
NPI 1740643378
Internal Medicine in Baltimore, MD

Active since March 31, 2016PECOS EnrolledAccepts Medicare Assignment
100/100
CMS Quality Rating
22 S GREENE ST, ROOM N3E09, BALTIMORE, MD 21201(410) 328-6110 Get Directions Write a Review

NPPES record last updated: December 20, 2021. Verified against the NPPES registry weekly; last sync: August 09, 2026.

Record update history: Dec 20, 2021, Sep 26, 2021, Mar 31, 2016 (3 updates tracked since 2016).

About William R Grier M.d NPPES

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

WILLIAM R GRIER M.D (NPI 1740643378) is an individual internal medicine provider in Baltimore, Maryland, licensed in Maryland (D91153) and active in the NPI registry since March 2016. He is enrolled in Medicare PECOS, is affiliated with University Of Maryland Medical Center, and maintains a secondary practice location in Glen Burnie.

NPPES Registry Identity

NPI1740643378
Entity TypeIndividualMale
Primary Taxonomy207R00000X
Provider Legal NameWILLIAM R GRIERCredential: M.D
Location Address22 S GREENE ST, ROOM N3E09Baltimore, MD 21201-1544
Mailing Address22 S Greene St, Room N3e09Baltimore, MD 21201-1544
Phone(410) 328-6110
Sole ProprietorNo
Medical School CMSDrexel University College Of MedicineGraduated 2016
Enumeration DateMarch 31, 2016
Last NPPES UpdateDecember 20, 20213 updates tracked since enumeration
NPPES CertifiedDecember 20, 2021
✔ NPI 1740643378 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in MD · D91153
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.
22 S GREENE ST, Baltimore, MD 21201
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Secondary Practice Location 1

Location 1301 Hospital DrGlen Burnie, MD 21061-5803 · Phone (410) 787-4000

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

William R Grier 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 ID3072892033
PECOS Enrollment IDI20210928002211
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 14

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.

Test to examine how well the lungs exchange gases 94729
This is a test called a pulmonary function test, which helps understand the efficiency of your lungs. It measures how much air your lungs can hold, how quickly you can move air in and out of your lungs, and how well your lungs put oxygen into and remove carbon dioxide from your blood.
117 services109 patients
Test to determine lung volumes using sensors 94726
This test, called spirometry, measures lung capacity using sensors. You breathe into a mouthpiece attached to a device that records the amount and rate of air you inhale and exhale. It helps diagnose and monitor lung conditions.
116 services108 patients
Test to measure expiratory airflow and volume 94010
This test, known as spirometry, assesses how well your lungs work. It measures how much air you can inhale, how much you can exhale and how quickly you can exhale. It's non-invasive and helps diagnose conditions like asthma or COPD.
104 services94 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.
69 services52 patients
Test to measure expiratory airflow and volume changes before and after medication administration 94060
This procedure measures how air flows in and out of your lungs. It's done before and after medication to see if the treatment improves your breathing. It's a simple, non-invasive test that involves breathing into a device called a spirometer.
53 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.
45 services25 patients

Hospital Affiliations CMS Care Compare 2

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

University Of Maryland Medical Center

Acute Care Hospitals · Baltimore, MD
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number210002
Location22 South Greene StreetBaltimore, MD 21201 · Baltimore City County
Emergency services Birthing friendly

University Of MD Medical Center Midtown Campus

Acute Care Hospitals · Baltimore, MD
3/5 CMS rating
OwnershipVoluntary non-profit - Other
CMS Certification Number210038
Location827 Linden AvenueBaltimore, MD 21201 · Baltimore City County
Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 21201 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
$139.05 typical visit price
range $60.73 – $183.44
Typical copayment $34.76 (range $15.18 – $45.86)
Most-billed visit code 99204
Established Patient
$106.59 typical visit price
range $19.60 – $149.17
Typical copayment $26.64 (range $4.90 – $37.29)
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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

100/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Promoting Interoperability100
Improvement Activities40

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.

DR. LEONARD ANANG SOWAH M.D.
Internal Medicine
22 S GREENE ST
BALTIMORE, MD 21201
Baltimore City (410) 706-4619
VISHAL BHATNAGAR MD
Student in an Organized Health Care Education/Training Program
22 S GREENE ST, MEDICINE, N3E09
BALTIMORE, MD 21201
Baltimore City (410) 328-6110
NANCE J FOX P.A.-C
Physician Assistant (Medical)
22 S GREENE ST, G2K36
BALTIMORE, MD 21201
Baltimore City (410) 328-1170
HILARY TAMARA WOLF MD
Pediatrics (Adolescent Medicine)
22 S GREENE ST
BALTIMORE, MD 21201
Baltimore City (410) 328-7373
MS. LINDSAY BREAM O'MEARA CRNP
Nurse Practitioner (Acute Care)
22 S GREENE ST, SUITE S4D07
BALTIMORE, MD 21201
Baltimore City (410) 328-3365
NORA T OLIVER M.D., M.P.H.
Student in an Organized Health Care Education/Training Program
22 S GREENE ST, N3E09
BALTIMORE, MD 21201
Baltimore City (410) 328-5756
SHOSHANA JO WEINER
Internal Medicine
22 S GREENE ST
BALTIMORE, MD 21201
Baltimore City (617) 214-1332
JENNA VANLIERE CANZONIERO M.D.
Internal Medicine
22 S GREENE ST, N3E09
BALTIMORE, MD 21201
Baltimore City (410) 328-5756

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 William Grier's NPI number?

The NPI number for William Grier is 1740643378. It was assigned to this individual provider in the NPPES registry on March 31, 2016.

Where is William Grier located?

William Grier practices at 22 S Greene St Room N3e09, Baltimore, MD 21201. The listed phone number is (410) 328-6110.

What is William Grier's specialty?

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

Is William Grier enrolled in Medicare?

Yes. William Grier 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 William Grier affiliated with any hospitals?

According to CMS data, William Grier is affiliated with University Of Maryland Medical Center and University Of MD Medical Center Midtown Campus.

When was this NPI record last updated?

The NPPES record for William Grier was last updated on December 20, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.