SHELLY CHRISTINA WILLIAMS-ISINGO FNP-BC, PMHNP-BC
NPI 1538680822
Nurse Practitioner - Psychiatric/Mental Health in Katy, TX
About Shelly Christina Williams-isingo Fnp-bc, Pmhnp-bc NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
SHELLY CHRISTINA WILLIAMS-ISINGO FNP-BC, PMHNP-BC (NPI 1538680822) is an individual psychiatric/mental health provider in Katy, Texas, licensed in Texas (AP138281) and active in the NPI registry since June 2017. She is enrolled in Medicare PECOS and is a graduate of Other (2017).
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 3
Accepted 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
Shelly Christina Williams-isingo Fnp-bc, Pmhnp-bc 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.
Medicare Billing Reassignments
7Medicare enrollment records show Shelly Williams-isingo reassigns Medicare billing to 7 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Fulshear, TX 77441
- Reassigned Medicare billing, Texas enrollment
- 3 clinicians in this Medicare group
Lake Charles, LA 70605
- Reassigned Medicare billing, Louisiana enrollment
- 314 clinicians in this Medicare group
Abbeville, LA 70510
- Reassigned Medicare billing, Louisiana enrollment
- 241 clinicians in this Medicare group
Jacksonville, FL 32256
- Reassigned Medicare billing, Florida enrollment
- 18 clinicians in this Medicare group
Allen Park, MI 48101
- Reassigned Medicare billing, Michigan enrollment
- Medicare enrollment name: Firsthand Health Of Michigan PC
- 20 clinicians in this Medicare group
Cleveland, OH 44125
- Reassigned Medicare billing, Ohio enrollment
- 19 clinicians in this Medicare group
Tacoma, WA 98402
- Reassigned Medicare billing, Washington enrollment
- 23 clinicians in this Medicare group
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 2
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.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 77494 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Referred Medical Equipment & Supplies CMS DME claims
Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.
Other Providers at the Same Location NPPES
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
KATY, TX 77494
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 Shelly Williams-isingo's NPI number?
The NPI number for Shelly Williams-isingo is 1538680822. It was assigned to this individual provider in the NPPES registry on June 27, 2017.
Where is Shelly Williams-isingo located?
Shelly Williams-isingo practices at 440 Cobia Dr Ste 602, Katy, TX 77494. The listed phone number is (713) 987-7828.
What is Shelly Williams-isingo's specialty?
The primary specialty registered for this NPI is Nurse Practitioner, specializing in Psychiatric/Mental Health, with taxonomy code 363LP0808X.
Is Shelly Williams-isingo enrolled in Medicare?
Yes. Shelly Williams-isingo 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.
Which organizations bill Medicare for Shelly Williams-isingo's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Shelly Williams-isingo reassigns Medicare benefits to 7 organizations: Mosaic Mental Health (Fulshear, TX), Calcasieu Urgent Care LLC (Lake Charles, LA), Hulin Urgent Care Services, LLC (Abbeville, LA), Firsthand Health Of Florida PA (Jacksonville, FL), Firsthand Health Of Michigan, P.C. (Allen Park, MI) and 2 more organizations, listed in the Medicare section above. Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Shelly Williams-isingo's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Shelly Williams-isingo accept?
Health plans from Cigna Healthcare and UnitedHealthcare list Shelly Williams-isingo 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.
When was this NPI record last updated?
The NPPES record for Shelly Williams-isingo was last updated on September 8, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 42 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.
# Shelly Christina Williams-Isingo, FNP-BC, PMHNP-BC · NPI 1538680822
Psychiatric/Mental Health physician in Katy, Texas. Individual provider, active in the CMS NPPES registry since June 27, 2017.
## Identity
- **NPI:** 1538680822 (Entity type: Individual)
- **Enumerated:** June 27, 2017
- **Primary specialty:** Nurse Practitioner - Psychiatric/Mental Health · taxonomy 363LP0808X
- **State license:** AP138281 (Texas)
- **Sole proprietor:** No
## Practice location
- **Address:** 440 COBIA DR STE 602, Katy, TX 77494-6892
- **Phone:** (713) 987-7828
## Medicare
- **Medicare:** Enrolled (PECOS); accepts Medicare assignment
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 7 organizations under Medicare reassignment (form CMS-855R): Mosaic Mental Health (NPI 1437733847, Fulshear, TX); Calcasieu Urgent Care LLC (NPI 1467715490, Lake Charles, LA); Hulin Urgent Care Services, LLC (NPI 1043768716, Abbeville, LA); Firsthand Health Of Florida PA (NPI 1316685605, Jacksonville, FL); Firsthand Health Of Michigan, P.C. (NPI 1184402745, Allen Park, MI); and 2 more · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2017
## Record status
- **NPPES last updated:** September 8, 2026
- **Other identifiers:** Other AP61561016 (WA); Other AP09322 (LA); Other AP138281 (TX)
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Source: [NPI Profile](https://npiprofile.com/npi/1538680822) · Data from the CMS NPPES public registry.