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WILLIAM P MUSTAS P.A.
NPI 1629080932
Physician Assistant in Waukesha, WI

Active since August 13, 2006PECOS EnrolledAccepts Medicare Assignment
82.39/100
CMS Quality Rating
1111 DELAFIELD ST STE 215, WAUKESHA, WI 53188(262) 542-0074(262) 542-2803 Get Directions Write a Review

NPPES record last updated: September 18, 2024. Verified against the NPPES registry weekly; last sync: August 09, 2026.

About William P Mustas P.a. NPPES

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

WILLIAM P MUSTAS P.A. (NPI 1629080932) is an individual physician assistant in Waukesha, Wisconsin, licensed in Wisconsin (1307) and active in the NPI registry since August 2006. He is enrolled in Medicare PECOS, is affiliated with Los Alamos Medical Center, and is a graduate of Other (2000).

NPPES Registry Identity

NPI1629080932
Entity TypeIndividualMale
Primary Taxonomy363A00000X
Provider Legal NameWILLIAM P MUSTASCredential: P.A.
Location Address1111 DELAFIELD ST STE 215Waukesha, WI 53188-3403
Mailing Address1111 Delafield St Ste 215Waukesha, WI 53188-3403 · (262) 542-0074 · Fax (262) 542-2803
Phone(262) 542-0074
Fax(262) 542-2803
Sole ProprietorYes
Medical School CMSOtherGraduated 2000
Enumeration DateAugust 13, 2006
Last NPPES UpdateSeptember 18, 2024
NPPES CertifiedSeptember 18, 2024
✔ NPI 1629080932 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyPhysician AssistantPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363A00000X
License✔ Licensed in WI · 1307
Definition
A physician assistant is a person who has successfully completed an accredited education program for physician assistant, is licensed by the state and is practicing within the scope of that license. Physician assistants are formally trained to perform many of the routine, time-consuming tasks a physician can do. In some states, they may prescribe medications. They take medical histories, perform physical exams, order lab tests and x-rays, and give inoculations. Most states require that they work under the supervision of a physician.
1111 DELAFIELD ST STE 215, Waukesha, WI 53188
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Other Identifiers 1

Other1703WI · License

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 P Mustas P.a. 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 ID8820211402
PECOS Enrollment IDI20250212001475
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 4

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 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.
76 services64 patients
Ultrasound measurement of bladder capacity after voiding 51798
Ultrasound measurement of bladder capacity after voiding is a non-invasive test that uses sound waves to create images of your bladder. It's done after you've emptied your bladder to see if there's any leftover urine, which can help diagnose certain conditions.
33 services31 patients
Automated urinalysis test 81003
An automated urinalysis test is a routine examination that checks your urine for various substances. It can help identify potential health issues such as kidney problems or diabetes. The test uses a machine to analyze a small urine sample, providing quick and accurate results.
20 services18 patients
Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes 99221
Initial hospital inpatient care refers to the first day of your stay in the hospital. This service typically includes a 30-minute check-up with a healthcare professional. They'll assess your health, discuss your condition, and plan your treatment. It's part of ensuring you receive the best possible care.
19 services18 patients

Hospital Affiliations CMS Care Compare

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

Los Alamos Medical Center

Acute Care Hospitals · Los Alamos, NM
OwnershipProprietary
CMS Certification Number320033
Location3917 West RoadLos Alamos, NM 87544 · Los Alamos County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 53188 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
$82.92 typical visit price
range $53.90 – $163.24
Typical copayment $20.73 (range $13.47 – $40.81)
Most-billed visit code 99203
Established Patient
$67.37 typical visit price
range $17.40 – $133.76
Typical copayment $16.84 (range $4.35 – $33.44)
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.

82.39/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice
Quality77.88
Promoting Interoperability81
Improvement Activities40
Cost74.38

Other Providers at the Same Location NPPES

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

MEGAN ROTH
Nurse Practitioner (Family)
1111 DELAFIELD ST STE 215
WAUKESHA, WI 53188
Waukesha County (262) 542-2594

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 Mustas's NPI number?

The NPI number for William Mustas is 1629080932. It was assigned to this individual provider in the NPPES registry on August 13, 2006.

Where is William Mustas located?

William Mustas practices at 1111 Delafield St Ste 215, Waukesha, WI 53188. The listed phone number is (262) 542-0074.

What is William Mustas's specialty?

The primary specialty registered for this NPI is Physician Assistant with taxonomy code 363A00000X.

Is William Mustas enrolled in Medicare?

Yes. William Mustas 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 Mustas affiliated with any hospitals?

According to CMS data, William Mustas is affiliated with Los Alamos Medical Center.

When was this NPI record last updated?

The NPPES record for William Mustas was last updated on September 18, 2024. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 22 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.