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

REX KEITH KESSLER M.D.
NPI 1841298023
Internal Medicine - Endocrinology, Diabetes & Metabolism in Aston, PA

Active since July 12, 2005PECOS Enrolled
95.75/100
CMS Quality Rating
2901 DUTTON MILL RD, STE 110, ASTON, PA 19014(610) 876-2300(610) 876-3004 Get Directions Write a Review

NPPES record last updated: July 26, 2026. Verified against the NPPES registry weekly; last sync: August 02, 2026.

About Rex Keith Kessler M.d. NPPES

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

REX KEITH KESSLER M.D. (NPI 1841298023) is an individual endocrinology, diabetes & metabolism provider in Aston, Pennsylvania, licensed in Pennsylvania (MD 020904E) and active in the NPI registry since July 2005. He is enrolled in Medicare PECOS, is affiliated with Bryn Mawr Hospital, and is a graduate of Temple University School Of Medicine (1977).

NPPES Registry Identity

NPI1841298023
Entity TypeIndividualMale
Primary Taxonomy207RE0101X
Provider Legal NameREX KEITH KESSLERCredential: M.D.
Location Address2901 DUTTON MILL RD, STE 110Aston, PA 19014-2849
Mailing AddressPo Box 1897Boothwyn, PA 19061-7897 · (610) 876-2300 · Fax (610) 876-3004
Phone(610) 876-2300
Fax(610) 876-3004
Sole ProprietorYes
Medical School CMSTemple University School Of MedicineGraduated 1977
Enumeration DateJuly 12, 2005
Last NPPES UpdateJuly 26, 2026
✔ NPI 1841298023 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Endocrinology, Diabetes & MetabolismAllopathic & Osteopathic Physicians
Taxonomy Code207RE0101X
License✔ Licensed in PA · MD 020904E
Definition
An internist who concentrates on disorders of the internal (endocrine) glands such as the thyroid and adrenal glands. This specialist also deals with disorders such as diabetes, metabolic and nutritional disorders, obesity, pituitary diseases and menstrual and sexual problems.
Also ListedInternal MedicineTaxonomy 207R00000X · License MD 020904E (PA)
2901 DUTTON MILL RD, Aston, PA 19014
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Other Identifiers 3

Other2769330/3545085PA · Aetna
Medicaid001612715-0006PA
Other2060988000PA · Keystone East

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Highmark Blue Cross Blue Shield Delaware.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

Rex Keith Kessler 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 ID3476507922
PECOS Enrollment IDI20050308000418
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 7

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.

Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 99231
Follow-up hospital inpatient care is a daily service where a healthcare professional checks on your health progress during your hospital stay. Each session typically lasts 15 minutes, involving updates on your condition and adjustments to your treatment plan, if necessary.
2,315 services266 patients
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232
Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.
951 services230 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.
360 services195 patients
Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222
Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.
139 services133 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.
119 services115 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.
41 services38 patients

Hospital Affiliations CMS Care Compare 4

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

Bryn Mawr Hospital

Acute Care Hospitals · Bryn Mawr, PA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number390139
Location130 South Bryn Mawr AveBryn Mawr, PA 19010 · Montgomery County
Emergency services Birthing friendly

Paoli Hospital

Acute Care Hospitals · Paoli, PA
5/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number390153
Location255 West Lancaster AvenuePaoli, PA 19301 · Chester County
Emergency services Birthing friendly

Main Line Hospital Lankenau

Acute Care Hospitals · Wynnewood, PA
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number390195
Location100 Lancaster AveWynnewood, PA 19096 · Montgomery County
Emergency services Birthing friendly

Riddle Memorial Hospital

Acute Care Hospitals · Media, PA
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number390222
Location1068 West Baltimore PikeMedia, PA 19063 · Delaware County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 19014 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
$137.17 typical visit price
range $59.88 – $180.99
Typical copayment $34.29 (range $14.97 – $45.24)
Most-billed visit code 99204
Established Patient
$105.21 typical visit price
range $19.30 – $147.29
Typical copayment $26.30 (range $4.82 – $36.82)
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.

95.75/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Promoting Interoperability95
Improvement Activities40

Reported Quality Measures

Preventive Care and Screening: Body Mass Index (BMI) Screening and Follow-Up Plan
Percentage of patients aged 18 years and older with a BMI documented during the current encounter or during the previous twelve months AND with a BMI outside of normal parameters, a follow-up plan is documented during the encounter or during the previous…
42%234 patients2/55-star benchmark: 100%
Providers report different measures because they deliver different services; reporting more or less information is not a reflection of quality. Star ratings appear only where CMS assigned them.

Referred Medical Equipment & Supplies CMS DME claims 4

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Blood glucose test or reagent strips for home blood glucose monitor, per 50 strips A4253
DME-Other DME · category DE017N
28 suppliers96 claims291 services$6.11 avg. paid by Medicare
Lancets, per box of 100 A4259
DME-Medical/Surgical Supplies · category DA000N
11 suppliers25 claims41 services$1.12 avg. paid by Medicare
Supply allowance for therapeutic continuous glucose monitor (cgm), includes all supplies and accessories, 1 month supply = 1 unit of service K0553
DME-Other DME · category DE017N
12 suppliers235 claims235 services$186.53 avg. paid by Medicare
Receiver (monitor), dedicated, for use with therapeutic glucose continuous monitor system K0554
DME-Other DME · category DE017N
6 suppliers12 claims12 services$174.48 avg. paid by Medicare
Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 10

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

REGINA MARY UBALDI-ROSEN MSN/CRNP
Nurse Practitioner (Family)
2901 DUTTON MILL RD
ASTON, PA 19014
Delaware County (610) 485-6700
SLEEP DENTISTRY CENTER P.C.
Dentist (General Practice)
2901 DUTTON MILL RD, SUITE 210
ASTON, PA 19014
Delaware County (610) 674-1800
RIDDLE ENDOCRINOLOGY & METABOLISM ASSOCIATES, PC
Internal Medicine (Endocrinology, Diabetes & Metabolism)
2901 DUTTON MILL RD, STE 110
ASTON, PA 19014
Delaware County (610) 876-2300
PROVIDENCE MEDICAL ASSOCIATES, INC
Internal Medicine
2901 DUTTON MILL RD, STE 110
ASTON, PA 19014
Delaware County (610) 876-2300
TRAN B TRUONG
Nurse Practitioner (Family)
2901 DUTTON MILL RD
ASTON, PA 19014
Delaware County (610) 485-6700
WALLINGFORD MEDICAL CLINIC, LLC
Internal Medicine
2901 DUTTON MILL RD, STE 110
ASTON, PA 19014
Delaware County (610) 876-2300
ROBERT KERNS
Dentist (Pediatric Dentistry)
2901 DUTTON MILL RD
ASTON, PA 19014
Delaware County (610) 485-9977
KESSLER ENDOCRINOLOGY ASSOC PC
Internal Medicine (Endocrinology, Diabetes & Metabolism)
2901 DUTTON MILL RD, STE 110
ASTON, PA 19014
Delaware County (610) 876-2300

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 Rex Kessler's NPI number?

The NPI number for Rex Kessler is 1841298023. It was assigned to this individual provider in the NPPES registry on July 12, 2005.

Where is Rex Kessler located?

Rex Kessler practices at 2901 Dutton Mill Rd Ste 110, Aston, PA 19014. The listed phone number is (610) 876-2300.

What is Rex Kessler's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Endocrinology, Diabetes & Metabolism, with taxonomy code 207RE0101X.

Is Rex Kessler enrolled in Medicare?

Yes. Rex Kessler 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 Rex Kessler accept?

Health plans from Highmark Blue Cross Blue Shield Delaware list Rex Kessler 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 Rex Kessler affiliated with any hospitals?

According to CMS data, Rex Kessler is affiliated with Bryn Mawr Hospital, Paoli Hospital, Main Line Hospital Lankenau and Riddle Memorial Hospital.

When was this NPI record last updated?

The NPPES record for Rex Kessler was last updated on July 26, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.