Billie Corwin, FNP-C
NPI 1881446631 · Family Nurse Practitioner · San Marcos, TX
Enrolled with Medicare as Practitioner - Nurse Practitioner · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Billie Corwin, FNP-C is a Family Nurse Practitioner provider in San Marcos, TX (NPI 1881446631).
Provider details
- NPI number
- 1881446631
- Entity type
- Individual
- Primary specialty
- Family Nurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers
- Credential
- FNP-C
- Sex
- Female
- Sole proprietor
- Yes
- License
- 1156416 (TX)
Specialties & taxonomies
Physician Assistants & Advanced Practice Nursing Providers
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure28% of score
2 yrs in NPPES registry
- Profile completeness28% of score
100% of core fields populated
- Practice footprint17% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)28% of score
13 Medicare services, 2024 (ranked within specialty)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Residence Visit for New Patient With High Level of Medical Decision Making, Per Day, If Using Time, at Least 75 Minutes99345 | 13 | $164 |
Typical Medicare-allowed amounts for these services range $164–$164 (2024). The Medicare-allowed amount is what Medicare recognizes for a service under fee-for-service — a reference figure for 2024, not a price quote and not what you would be billed. Medicare Part B covers roughly an eighth of all NPIs (65+ skew); services with fewer than 11 beneficiaries are suppressed by CMS. Source: CMS Medicare Physician & Other Practitioners, by Provider & Service.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 10 distinct drugs on file.
| Drug | Part D claims (2024) |
|---|---|
| Potassium Chloride | 26 |
| Donepezil Hcl | 22 |
| Gabapentin | 16 |
| Levothyroxine Sodium | 14 |
| Amlodipine Besylate | 13 |
| Semaglutidebrand: Ozempic | 13 |
| Trazodone Hcl | 13 |
| Escitalopram Oxalate | 11 |
| Famotidine | 11 |
Practice location
Mailing address
Registry dates
- Enumerated
- 2024-04-04
- Last updated
- 2026-05-14
- Certified
- 2026-05-14
Frequently asked questions
- What is Billie Corwin's NPI number?
- Billie Corwin's National Provider Identifier (NPI) is 1881446631, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Billie Corwin's specialty?
- Billie Corwin is listed in the NPPES registry with a primary specialty of Family Nurse Practitioner (Physician Assistants & Advanced Practice Nursing Providers).
- Where is Billie Corwin located?
- Billie Corwin's practice location on file with NPPES is 151 Stagecoach Trl Ste 105, San Marcos, TX 78666-3863.
- What is Billie Corwin's phone number?
- The practice phone number listed in the NPPES registry for Billie Corwin is (737) 213-1271.
- Does Billie Corwin accept Medicare?
- Billie Corwin is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Billie Corwin's NPI active?
- Yes — Billie Corwin's NPI (1881446631) is active in the NPPES registry as of the last update on 2026-05-14.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.