MARIO JOSE CASTELLANOS MD
NPI 1164050910
Emergency Medicine in Boston, MA
About Mario Jose Castellanos Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARIO JOSE CASTELLANOS MD (NPI 1164050910) is an individual emergency medicine provider in Boston, Massachusetts, licensed in Massachusetts (289097) and active in the NPI registry since March 2020. He is enrolled in Medicare PECOS, is affiliated with Faulkner Hospital-brigham And Women's, and maintains a secondary practice location in Boston.
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
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
Mario Jose Castellanos Md 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
3Medicare enrollment records show Mario Castellanos reassigns Medicare billing to 3 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Boston, MA 02115
- Reassigned Medicare billing, Massachusetts enrollment
- 4,574 clinicians in this Medicare group
Boston, MA 02114
- Reassigned Medicare billing, Massachusetts enrollment
- 6,234 clinicians in this Medicare group
Boston, MA 02114
- Reassigned Medicare billing, Massachusetts enrollment
- 6,360 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.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Faulkner Hospital-Brigham And Women's
Acute Care Hospitals · Boston, MAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 02115 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Other Providers at the Same Location NPPES 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BOSTON, MA 02115
BOSTON, MA 02115
BOSTON, MA 02115
BOSTON, MA 02115
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 Mario Castellanos's NPI number?
The NPI number for Mario Castellanos is 1164050910. It was assigned to this individual provider in the NPPES registry on March 28, 2020.
Where is Mario Castellanos located?
Mario Castellanos practices at 75 Francis St, Boston, MA 02115. The listed phone number is (617) 732-5500.
What is Mario Castellanos's specialty?
The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.
Is Mario Castellanos enrolled in Medicare?
Yes. Mario Castellanos 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 Mario Castellanos's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mario Castellanos reassigns Medicare benefits to 3 organizations: Brigham & Womens Physicians Organization Inc (Boston, MA), The General Hospital Corporation (Boston, MA) and Massachusetts General Physicians Organization Inc (Boston, MA). 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 Mario Castellanos's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Mario Castellanos accept?
Health plans from Taro Health list Mario Castellanos 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 Mario Castellanos affiliated with any hospitals?
According to CMS data, Mario Castellanos is affiliated with Faulkner Hospital-Brigham And Women's.
When was this NPI record last updated?
The NPPES record for Mario Castellanos was last updated on June 23, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.
# Mario Jose Castellanos, MD · NPI 1164050910
Emergency Medicine physician in Boston, Massachusetts. Individual provider, active in the CMS NPPES registry since March 28, 2020.
## Identity
- **NPI:** 1164050910 (Entity type: Individual)
- **Enumerated:** March 28, 2020
- **Primary specialty:** Emergency Medicine · taxonomy 207P00000X
- **State license:** 289097 (Massachusetts)
- **Sole proprietor:** No
## Practice location
- **Address:** 75 FRANCIS ST, Boston, MA 02115-6110
- **Phone:** (617) 732-5500
## 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:** 3 organizations under Medicare reassignment (form CMS-855R): Brigham & Womens Physicians Organization Inc (NPI 1033535497, Boston, MA); The General Hospital Corporation (NPI 1023049236, Boston, MA); Massachusetts General Physicians Organization Inc (NPI 1801874573, Boston, MA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Medical College Of Wisconsin, class of 2021
## Record status
- **NPPES last updated:** June 23, 2025
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Source: [NPI Profile](https://npiprofile.com/npi/1164050910) · Data from the CMS NPPES public registry.