Quick answers
- Does Mariles Viloria-Grageda accept Medicare assignment?
- Yes. Medicare's clinician data says Mariles Viloria-Grageda 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.
- What is Mariles Viloria-Grageda's NPI number?
- 1255371738. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Practice locations
Addresses where Mariles Viloria-Grageda is enrolled with Medicare (CMS data updated October 2, 2026).
- 8221 Willow Oaks Corporate DrFairfax, VA 22031 (703) 289‑7560
- 8505 Arlington BlvdFairfax, VA 22031
Group practices
Medicare enrollment lists Mariles Viloria-Grageda as a member of this group (CMS data updated October 2, 2026).
- Inova Health Care Services1,817 clinicians in the group
Specialties
- Psychiatryprimary
- Neurologyalso
Other psychiatrists in Fairfax
Clinicians with the same Medicare primary specialty in Fairfax, VA — not a recommendation.
Other clinicians in Inova Health Care Services
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 1978 (48 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1255371738 |
| 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
- 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