DR. MARY ANN WILLIAMSON M.D.
NPI 1598931206
Internal Medicine - Cardiovascular Disease in Doylestown, PA

Active since May 02, 2008PECOS EnrolledAccepts Medicare Assignment
315 W STATE ST, DOYLESTOWN, PA 18901(215) 345-1900 Get Directions Write a Review

NPPES record last updated: June 15, 2015. Verified against the NPPES registry weekly; last sync: November 08, 2026.

About Dr. Mary Ann Williamson M.d. NPPES

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

DR. MARY ANN WILLIAMSON M.D. (NPI 1598931206) is an individual cardiovascular disease provider in Doylestown, Pennsylvania, licensed in Pennsylvania (MD448085) and active in the NPI registry since May 2008. She is enrolled in Medicare PECOS, is affiliated with Doylestown Hospital, and is a graduate of Other (2006).

NPPES Registry Identity

NPI1598931206
Entity TypeIndividualFemale
Primary Taxonomy207RC0000X
Provider Legal NameDR. MARY ANN WILLIAMSONCredential: M.D.
Location Address315 W STATE STDoylestown, PA 18901-3525
Mailing Address315 W State StDoylestown, PA 18901-3525 · (215) 345-1900
Sole ProprietorNo
Medical School CMSOtherGraduated 2006
Enumeration DateMay 2, 2008
Last NPPES UpdateJune 15, 2015
✔ NPI 1598931206 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Cardiovascular DiseaseAllopathic & Osteopathic Physicians
Taxonomy Code207RC0000X
License✔ Licensed in PA · MD448085
Definition
An internist who specializes in diseases of the heart and blood vessels and manages complex cardiac conditions such as heart attacks and life-threatening, abnormal heartbeat rhythms.
315 W STATE ST, Doylestown, PA 18901

Other Identifiers 2

Medicaid1028437000001PA
Medicare PIN293209K3HPA

Accepted Insurance

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. Mary Ann Williamson 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 ID3173679644
PECOS Enrollment IDI20130727000034
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

2

Medicare enrollment records show Mary Ann Williamson reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Obstetrics & Gynecology
102 PROGRESS DR STE 202
Doylestown, PA 18901
  • Reassigned Medicare billing, Pennsylvania enrollment
  • 192 clinicians in this Medicare group
Obstetrics & Gynecology
102 PROGRESS DR STE 101
Doylestown, PA 18901
  • Reassigned Medicare billing, Pennsylvania enrollment
  • 268 clinicians in this Medicare group

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 28

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.

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.
545 services420 patients
Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report 93000
An electrocardiogram (ECG) is a non-invasive test that records your heart's electrical activity. Using 12 leads attached to your body, it captures data to help identify heart conditions. A doctor interprets the results and provides a report.
460 services425 patients
Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only 93010
A routine electrocardiogram (ECG) with 12 leads is a simple, non-invasive test that records the electrical activity of your heart. It helps in identifying heart conditions by detecting irregularities in your heart rhythms. The results are interpreted and a report is provided.
388 services316 patients
Ultrasound of heart with color-depicted blood flow, rate, direction and valve function 93306
This is a heart ultrasound, also known as an echocardiogram. It uses sound waves to create pictures of your heart, showing how blood flows through it. The color depicts the blood flow's speed and direction. It also checks the heart's valves to ensure they're working properly.
275 services273 patients
Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233
Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.
187 services120 patients
Ultrasound of heart with color-depicted blood flow, rate, direction and valve function 93306
This is a heart ultrasound, also known as an echocardiogram. It uses sound waves to create pictures of your heart, showing how blood flows through it. The color depicts the blood flow's speed and direction. It also checks the heart's valves to ensure they're working properly.
145 services144 patients

Hospital Affiliations CMS Care Compare

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

Doylestown Hospital

Acute Care Hospitals · Doylestown, PA
4/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number390203
Location595 West State StDoylestown, PA 18901 · Bucks County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 18901 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
$74.47 typical visit price
range $19.30 – $147.29
Typical copayment $18.61 (range $4.82 – $36.82)
Most-billed visit code 99213
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.

Internal Medicine (Cardiovascular Disease)
315 W STATE ST
DOYLESTOWN, PA 18901
Internal Medicine (Cardiovascular Disease)
315 W STATE ST
DOYLESTOWN, PA 18901
Internal Medicine (Cardiovascular Disease)
315 W STATE ST
DOYLESTOWN, PA 18901
Internal Medicine (Cardiovascular Disease)
315 W STATE ST
DOYLESTOWN, PA 18901
Internal Medicine (Cardiovascular Disease)
315 W STATE ST
DOYLESTOWN, PA 18901
Nurse Practitioner
315 W STATE ST
DOYLESTOWN, PA 18901
Internal Medicine (Cardiovascular Disease)
315 W STATE ST
DOYLESTOWN, PA 18901
Internal Medicine (Interventional Cardiology)
315 W STATE ST
DOYLESTOWN, PA 18901

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 Ann Williamson's NPI number?

The NPI number for Mary Ann Williamson is 1598931206. It was assigned to this individual provider in the NPPES registry on May 2, 2008.

Where is Mary Ann Williamson located?

Mary Ann Williamson practices at 315 W State St, Doylestown, PA 18901. The listed phone number is (215) 345-1900.

What is Mary Ann Williamson's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Cardiovascular Disease, with taxonomy code 207RC0000X.

Is Mary Ann Williamson enrolled in Medicare?

Yes. Mary Ann Williamson 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 Mary Ann Williamson's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Mary Ann Williamson reassigns Medicare benefits to 2 organizations: Clinical Specialty Associates (Doylestown, PA) and Via Affiliates (Doylestown, PA). 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 Mary Ann Williamson's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Mary Ann Williamson accept?

Health plans from Ambetter Health and Ambetter from Buckeye Health Plan list Mary Ann Williamson 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 Ann Williamson affiliated with any hospitals?

According to CMS data, Mary Ann Williamson is affiliated with Doylestown Hospital.

When was this NPI record last updated?

The NPPES record for Mary Ann Williamson was last updated on June 15, 2015. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.