WILLIAM MULLEN MD
NPI 1457362329
Internal Medicine - Cardiovascular Disease in Santa Clara, CA

Q: What is William Mullen's NPI number?

The NPI number for William Mullen is 1457362329. It was assigned to this individual provider in the NPPES registry on August 10, 2006.

Q: What is William Mullen's specialty?

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

Q: When was this NPI record last updated?

The NPPES record for William Mullen was last updated on October 22, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 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.

Active since August 10, 2006PECOS EnrolledAccepts Medicare Assignment

100/100

CMS Quality Rating

2441 MISSION COLLEGE BLVD, SANTA CLARA, CA 95054(800) 478-8837 Get Directions Write a Review

NPPES record last updated: October 22, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Feb 17, 2021, Apr 6, 2019 (2 updates tracked since 2019).

On this page

About William Mullen Md NPPES

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

WILLIAM MULLEN MD (NPI 1457362329) is an individual cardiovascular disease provider in Santa Clara, California, licensed in California (A43317) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS and is a graduate of Tulane University School Of Medicine (1984).

NPPES Registry Identity

NPI1457362329

Entity TypeIndividualMale

Primary Taxonomy207RC0000X

Provider Legal NameWILLIAM MULLENCredential: MD

Location Address2441 MISSION COLLEGE BLVDSanta Clara, CA 95054-1214

Mailing AddressPo Box 276950Sacramento, CA 95827-6950

Phone(800) 478-8837

Sole ProprietorNo

Medical School CMSTulane University School Of MedicineGraduated 1984

Enumeration DateAugust 10, 2006

Last NPPES UpdateOctober 22, 20252 updates tracked since enumeration

NPPES CertifiedOctober 22, 2025

✔ NPI 1457362329 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 CA · A43317

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.

2441 MISSION COLLEGE BLVD, Santa Clara, CA 95054

Open in Google Maps ↗

Other Identifiers 1

Medicaid145965100WY

Accepted Insurance

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

William Mullen Md 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 ID345234290

PECOS Enrollment IDI20040413000870

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 William Mullen reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Sutter Bay Medical Foundation

6.1 mi

Ambulatory Surgical

701 E EL CAMINO REAL, SUITE 1 NORTHWEST
Mountain View, CA 94040

Reassigned Medicare billing, California enrollment
Also billed through NPI 1568851327 (California), NPI 1043654486 (California), NPI 1033817168 (California), NPI 1306241534 (California), NPI 1013950807 (California)
373 clinicians in this Medicare group

NPI 1982845186 (650) 404-8444

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 15

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.

423 services303 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.

407 services399 patients

Evaluation of single, dual, multiple lead or leadless pacemaker system, remote up to 90 days 93294

This procedure evaluates your pacemaker system remotely for up to 90 days. It checks whether single, dual, multiple lead, or leadless pacemakers are working properly. It's a safe, convenient way to ensure your heart device is functioning optimally.

135 services64 patients

New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more 99205

This is a first-time patient visit where a healthcare professional spends 60-74 minutes with you. It involves a comprehensive evaluation, including your medical history and current health condition. They'll also advise on preventive health measures and formulate a treatment plan if needed.

90 services90 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.

80 services69 patients

Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215

This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.

67 services59 patients

Electrocardiogram (ecg) up to 30 days continuous with symptom monitoring, transmission and review and report by health care professional 93272

An Electrocardiogram (ECG) is a test that records the electrical activity of your heart. For up to 30 days, a device will continuously monitor your heart's rhythm, noting any symptoms. The data is sent to a healthcare professional who reviews it and provides a report on your heart health.

64 services63 patients

Evaluation of single, dual, or multiple lead implantable defibrillator system, remote up to 90 days 93295

This procedure involves remotely monitoring your implantable defibrillator system, which can have single, dual, or multiple leads. Over a period of up to 90 days, the system's performance is evaluated to ensure it's working properly and providing the necessary heart rhythm support.

45 services23 patients

Insertion of needle into vein for collection of blood sample 36415

This procedure involves inserting a small needle into a vein, typically in your arm, to collect a blood sample. It's a quick and simple process to help diagnose or monitor health conditions. You may feel a small prick, but discomfort is minimal.

39 services36 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.

33 services31 patients

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.

22 services22 patients

Electrocardiogram (ecg) 2-day continuous with review by health care professional 93227

An Electrocardiogram (ECG) is a test that checks your heart's activity. The 2-day continuous ECG records your heart's rhythm non-stop for 48 hours. It helps to detect irregularities that may not occur during a shorter test. A healthcare professional will review the results to identify any issues.

20 services20 patients

External shock to heart to regulate heart beat 92960

This procedure, known as cardioversion, uses an external electrical shock to restore your heart's normal rhythm. It's typically performed when irregular heartbeats, or arrhythmias, are causing severe symptoms and aren't responding to medications.

15 services12 patients

Ultrasound of heart, follow-up 93308

A follow-up ultrasound of the heart, also known as an echocardiogram, is a non-invasive test that uses sound waves to create images of your heart. It helps doctors monitor your heart's function and structures after initial assessment or treatment.

15 services15 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.

14 services13 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 95054 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

$156.67 typical visit price

range $70.37 – $206.04

Typical copayment $39.16 (range $17.59 – $51.51)

Most-billed visit code 99204

Established Patient

$86.56 typical visit price

range $23.96 – $169.60

Typical copayment $21.64 (range $5.99 – $42.40)

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.

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 Interoperability

100

Improvement Activities

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.

SIREESHA INDUPURU REDDY M.D.

Family Medicine