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MR. WILLIAM TANNER SLAY
NPI 1902696123
Physician Assistant in Jackson, MS

Active since May 09, 2025PECOS EnrolledAccepts Medicare Assignment
501 MARSHALL ST STE 301, JACKSON, MS 39202(601) 353-9900 Get Directions Write a Review

NPPES record last updated: August 26, 2025. Verified against the NPPES registry weekly; last sync: August 02, 2026.

About Mr. William Tanner Slay NPPES

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

MR. WILLIAM TANNER SLAY (NPI 1902696123) is an individual physician assistant in Jackson, Mississippi, licensed in Mississippi (PA00921) and active in the NPI registry since May 2025. He is enrolled in Medicare PECOS, is affiliated with Mississippi Baptist Medical Center, and is a graduate of Other (2025).

NPPES Registry Identity

NPI1902696123
Entity TypeIndividualMale
Primary Taxonomy363A00000X
Provider Legal NameMR. WILLIAM TANNER SLAY
Location Address501 MARSHALL ST STE 301Jackson, MS 39202-1687
Mailing Address2214 5th Street Rosenbaum Bldg RosenbMeridian, MS 39301 · (601) 484-0100
Phone(601) 353-9900
Sole ProprietorNo
Medical School CMSOtherGraduated 2025
Enumeration DateMay 9, 2025
Last NPPES UpdateAugust 26, 2025
NPPES CertifiedAugust 26, 2025
✔ NPI 1902696123 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 MS · PA00921
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.
501 MARSHALL ST STE 301, Jackson, MS 39202
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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Arkansas Health & Wellness, Ambetter from Louisiana Healthcare Connections, Ambetter from Magnolia Health and more.Insurance ›

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

Mr. William Tanner Slay 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 ID5193228500
PECOS Enrollment IDI20250911003472
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.

Hospital Affiliations CMS Care Compare

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

Mississippi Baptist Medical Center

Acute Care Hospitals · Jackson, MS
2/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number250102
Location1225 N State StJackson, MS 39202 · Hinds County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 39202 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
$80.50 typical visit price
range $51.65 – $159.18
Typical copayment $20.12 (range $12.91 – $39.79)
Most-billed visit code 99203
Established Patient
$64.96 typical visit price
range $16.15 – $129.61
Typical copayment $16.24 (range $4.03 – $32.40)
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.

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.

DR. KIERAN HYNES MD
Urology
501 MARSHALL ST STE 301
JACKSON, MS 39202
Hinds County (601) 353-9900
MATTHEW C MOSS MD
Urology
501 MARSHALL ST STE 301
JACKSON, MS 39202
Hinds County (601) 353-9900
SETH B STUART NP
Nurse Practitioner
501 MARSHALL ST STE 301
JACKSON, MS 39202
Hinds County (601) 353-9900

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 Slay's NPI number?

The NPI number for William Slay is 1902696123. It was assigned to this individual provider in the NPPES registry on May 9, 2025.

Where is William Slay located?

William Slay practices at 501 Marshall St Ste 301, Jackson, MS 39202. The listed phone number is (601) 353-9900.

What is William Slay's specialty?

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

Is William Slay enrolled in Medicare?

Yes. William Slay 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.

What insurance does William Slay accept?

Health plans from Ambetter from Arkansas Health & Wellness, Ambetter from Louisiana Healthcare Connections, Ambetter from Magnolia Health, Ambetter of Alabama and Ambetter of Tennessee and 2 other insurers list William Slay 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 William Slay affiliated with any hospitals?

According to CMS data, William Slay is affiliated with Mississippi Baptist Medical Center.

When was this NPI record last updated?

The NPPES record for William Slay was last updated on August 26, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 11 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.