Quick answers
- Does Ana M. Ballester Fiallo accept Medicare assignment?
- Yes. Medicare's clinician data says Ana M. Ballester Fiallo accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Ana M. Ballester Fiallo see?
- In 2024, CMS data shows 51 Original Medicare patients and 496 services for Ana M. Ballester Fiallo. This counts Original Medicare only and measures volume, not quality.
- What is Ana M. Ballester Fiallo's NPI number?
- 1811007412. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Ana M. Ballester Fiallo, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 51 |
|---|---|
| Services billed to Medicare | 496 |
| Different services or procedures | 44 |
| Participating Medicare provider | Yes |
| Average age of these patients | 75 |
Most frequent services
- Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)115 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- Arthritis75%
- High blood pressure71%
- High cholesterol71%
- Chronic kidney disease45%
- Diabetes39%
- Osteoporosis37%
Practice locations
Addresses where Ana M. Ballester Fiallo is enrolled with Medicare (CMS data updated October 2, 2026).
- 1130 Goliad Rd, Gonzaba Medical GroupSan Antonio, TX 78223 (210) 921‑3800
- 902 Bandera RdSan Antonio, TX 78228 (210) 431‑4503
Group practices
Medicare enrollment lists Ana M. Ballester Fiallo as a member of this group (CMS data updated October 2, 2026).
- GMG Health Systems Associates PA117 clinicians in the group
Specialties
- Rheumatologyprimary
Other rheumatologists in San Antonio
Clinicians with the same Medicare primary specialty in San Antonio, TX — not a recommendation.
Other clinicians in GMG Health Systems Associates PA
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | University Of Puerto Rico School Of Medicine |
| Graduation year | 1982 (44 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1811007412 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians