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

CASSY JEAN WILLIAMS APRN
NPI 1356617815
Nurse Practitioner in Boston, MA

Q: What is Cassy Williams's NPI number?

The NPI number for Cassy Williams is 1356617815. It was assigned to this individual provider in the NPPES registry on March 29, 2012.

Q: What is Cassy Williams's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Q: When was this NPI record last updated?

The NPPES record for Cassy Williams was last updated on August 12, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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 March 29, 2012PECOS EnrolledAccepts Medicare Assignment

68 HARRISON AVE STE 600, BOSTON, MA 02111(657) 500-0634(844) 705-0129 Get Directions Write a Review

NPPES record last updated: August 12, 2026. Verified against the NPPES registry weekly; last sync: August 23, 2026.

Record update history: Aug 12, 2026, Jun 4, 2025, Dec 3, 2021 and 5 more (8 updates tracked since 2019).

On this page

About Cassy Jean Williams Aprn NPPES

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

CASSY JEAN WILLIAMS APRN (NPI 1356617815) is an individual nurse practitioner in Boston, Massachusetts, licensed in Kentucky (3013217) and active in the NPI registry since March 2012. She is enrolled in Medicare PECOS, maintains 6 additional practice locations, and is a graduate of Other (2016).

NPPES Registry Identity

NPI1356617815

Entity TypeIndividualFemale

Primary Taxonomy363L00000X

Provider Legal NameCASSY JEAN WILLIAMSCredential: APRN

Location Address68 HARRISON AVE STE 600Boston, MA 02111-1995

Mailing Address13885 Saint John RdRineyville, KY 40162-9719 · (270) 312-8189

Phone(657) 500-0634

Fax(844) 705-0129

Sole ProprietorYes

Medical School CMSOtherGraduated 2016

Enumeration DateMarch 29, 2012

Last NPPES UpdateAugust 12, 20268 updates tracked since enumeration

NPPES CertifiedAugust 12, 2026

✔ NPI 1356617815 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyNurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers

Taxonomy Code363L00000X

License✔ Licensed in KY · 3013217

Definition

(1) A registered nurse provider with a graduate degree in nursing prepared for advanced practice involving independent and interdependent decision making and direct accountability for clinical judgment across the health care continuum or in a certified specialty. (2) A registered nurse who has completed additional training beyond basic nursing education and who provides primary health care services in accordance with state nurse practice laws or statutes. Tasks performed by nurse practitioners vary with practice requirements mandated by geographic, political, economic, and social factors. Nurse practitioner specialists include, but are not limited to, family nurse practitioners, gerontological nurse practitioners, pediatric nurse practitioners, obstetric-gynecologic nurse practitioners, and school nurse practitioners.

Also ListedNurse Practitioner · Acute CareTaxonomy 363LA2100X · License 3013217 (KY)

68 HARRISON AVE STE 600, Boston, MA 02111

Open in Google Maps ↗

Secondary Practice Locations 6

Location 14145 SW Watson Ave Ste 350Beaverton, OR 97005-2191 · Phone (857) 289-9374

Location 22021 Guadalupe St Ste 260Austin, TX 78705-5654 · Phone (346) 214-1790

Location 31580 N Logan St Fl 6Denver, CO 80203-1939 · Phone (720) 807-0053

Location 4506 2nd Ave Ste 1400Seattle, WA 98104-2329 · Phone (857) 289-9374

Location 52415 E Camelback Rd Ste 700Phoenix, AZ 85016-4245 · Phone (480) 690-9522

Location 62033 Gateway Pl Fl 5San Jose, CA 95110-3709 · Phone (857) 289-9374

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

Cassy Jean Williams Aprn 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 ID4284977935

PECOS Enrollment IDI20190520002941

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.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02111 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

$97.64 typical visit price

range $63.72 – $189.86

Typical copayment $24.41 (range $15.93 – $47.46)

Most-billed visit code 99203

Established Patient

$111.18 typical visit price

range $21.07 – $155.29

Typical copayment $27.79 (range $5.26 – $38.82)

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.

Other Providers at the Same Location NPPES 3

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

CURTIS WELLING P.A.

Physician Assistant

68 HARRISON AVE STE 600
BOSTON, MA 02111

Suffolk County (657) 500-0634

KRISTYN KULICK PA-C

Physician Assistant

68 HARRISON AVE STE 600
BOSTON, MA 02111

Suffolk County (657) 500-0634

MELISSA MILLER

Nurse Practitioner

68 HARRISON AVE STE 600
BOSTON, MA 02111

Suffolk County (657) 500-0634

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 Cassy Williams's NPI number?

The NPI number for Cassy Williams is 1356617815. It was assigned to this individual provider in the NPPES registry on March 29, 2012.

Where is Cassy Williams located?

Cassy Williams practices at 68 Harrison Ave Ste 600, Boston, MA 02111. The listed phone number is (657) 500-0634.

What is Cassy Williams's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Is Cassy Williams enrolled in Medicare?

Yes. Cassy Williams 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.

When was this NPI record last updated?

The NPPES record for Cassy Williams was last updated on August 12, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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.