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

MARISSA WILLIAMS PA-C
NPI 1851688873
Physician Assistant in Zephyrhills, FL

Q: What is Marissa Williams's NPI number?

The NPI number for Marissa Williams is 1851688873. It was assigned to this individual provider in the NPPES registry on June 29, 2011.

Q: What is Marissa Williams's specialty?

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

Q: When was this NPI record last updated?

The NPPES record for Marissa Williams was last updated on June 16, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 56 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.

Active since June 29, 2011PECOS Enrolled

7213 GREEN SLOPE DR, ZEPHYRHILLS, FL 33541(813) 355-4914(855) 547-5415 Get Directions Write a Review

NPPES record last updated: June 16, 2026. Verified against the NPPES registry weekly; last sync: August 09, 2026.

Record update history: Mar 20, 2020, Jul 15, 2016 (2 updates tracked since 2016).

On this page

About Marissa Williams Pa-c NPPES

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

MARISSA WILLIAMS PA-C (NPI 1851688873) is an individual physician assistant in Zephyrhills, Florida, licensed in Florida (PA9106109) and active in the NPI registry since June 2011. She is enrolled in Medicare PECOS, is affiliated with Florida Hospital Zephyrhills, and is a graduate of Other (2011).

NPPES Registry Identity

NPI1851688873

Entity TypeIndividualFemale

Primary Taxonomy363A00000X

Provider Legal NameMARISSA WILLIAMSCredential: PA-C

Location Address7213 GREEN SLOPE DRZephyrhills, FL 33541-1306

Mailing Address7213 Green Slope DrZephyrhills, FL 33541-1306 · (813) 355-4914 · Fax (855) 547-5415

Phone(813) 355-4914

Fax(855) 547-5415

Sole ProprietorNo

Medical School CMSOtherGraduated 2011

Enumeration DateJune 29, 2011

Last NPPES UpdateJune 16, 20262 updates tracked since enumeration

NPPES CertifiedJune 16, 2026

✔ NPI 1851688873 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 FL · PA9106109

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.

7213 GREEN SLOPE DR, Zephyrhills, FL 33541

Open in Google Maps ↗

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include UnitedHealthcare.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Marissa Williams Pa-c is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

PECOS PAC ID7618126392

PECOS Enrollment IDI20121015000011

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

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.

17 services17 patients

Hospital Affiliations CMS Care Compare 3

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

Florida Hospital Zephyrhills

Acute Care Hospitals · Zephyrhills, FL

5/5 CMS rating

OwnershipVoluntary non-profit - Church

CMS Certification Number100046

Location7050 Gall BlvdZephyrhills, FL 33541 · Pasco County

Emergency services Birthing friendly

Adventhealth Tampa

Acute Care Hospitals · Tampa, FL

2/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number100173

Location3100 E Fletcher AveTampa, FL 33613 · Hillsborough County

Emergency services Birthing friendly

Adventhealth Dade City

Acute Care Hospitals · Dade City, FL

4/5 CMS rating

OwnershipProprietary

CMS Certification Number100211

Location13100 Ft King RdDade City, FL 33525 · Pasco County

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 33541 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

$87.62 typical visit price

range $56.00 – $171.84

Typical copayment $21.90 (range $14.00 – $42.96)

Most-billed visit code 99203

Established Patient

$70.04 typical visit price

range $17.57 – $139.16

Typical copayment $17.51 (range $4.39 – $34.79)

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.

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

6 suppliers25 claims51 services$5.83 avg. paid by Medicare

Portable gaseous oxygen system, rental; includes portable container, regulator, flowmeter, humidifier, cannula or mask, and tubing E0431

DME-Oxygen and Supplies · category DC000N

3 suppliers26 claims26 services$13.71 avg. paid by Medicare

Continuous positive airway pressure (cpap) device E0601

DME-Other DME · category DE001N

2 suppliers12 claims12 services$41.23 avg. paid by Medicare

Oxygen concentrator, single delivery port, capable of delivering 85 percent or greater oxygen concentration at the prescribed flow rate E1390

DME-Oxygen and Supplies · category DC002N

3 suppliers27 claims27 services$63.45 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 5

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

CALVIN ZHANG PA-C

Physician Assistant