DR. MARY DERRANE MD
NPI 1366637084
Emergency Medicine in New Milford, CT
About Dr. Mary Derrane Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. MARY DERRANE MD (NPI 1366637084) is an individual emergency medicine provider in New Milford, Connecticut, licensed in Connecticut (045768) and active in the NPI registry since September 2007. She is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Other Names 1
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Dr. Mary Derrane Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
4Medicare enrollment records show Mary Derrane reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Torrington, CT 06790
- Reassigned Medicare billing, Connecticut enrollment
- 374 clinicians in this Medicare group
Norwalk, CT 06850
- Reassigned Medicare billing, Connecticut enrollment
- 113 clinicians in this Medicare group
Avon, CT 06001
- Reassigned Medicare billing, Connecticut enrollment
- 182 clinicians in this Medicare group
New Britain, CT 06052
- Reassigned Medicare billing, Connecticut enrollment
- 745 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 3
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 06776 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 2
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
NEW MILFORD, CT 06776
NEW MILFORD, CT 06776
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 Mary Derrane's NPI number?
The NPI number for Mary Derrane is 1366637084. It was assigned to this individual provider in the NPPES registry on September 6, 2007. The provider is also known as Dr. Mary Mackessy MD.
Where is Mary Derrane located?
Mary Derrane practices at 21 Elm Street, New Milford, CT 06776. The listed phone number is (860) 350-7222.
What is Mary Derrane's specialty?
The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.
Is Mary Derrane enrolled in Medicare?
Yes. Mary Derrane is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Mary Derrane's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Mary Derrane reassigns Medicare benefits to 4 organizations: The Charlotte Hungerford Hospital (Torrington, CT), Norwalk Hospital Association (Norwalk, CT), Hartford Healthcare Urgent Care Centers, LLC (Avon, CT) and The Hospital Of Central Connecticut At New Britain General And Bradley (New Britain, CT). 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 Mary Derrane's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Mary Derrane was last updated on August 8, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 14 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.
# Dr. Mary Derrane, MD · NPI 1366637084
Emergency Medicine physician in New Milford, Connecticut. Individual provider, active in the CMS NPPES registry since September 6, 2007.
## Identity
- **NPI:** 1366637084 (Entity type: Individual)
- **Enumerated:** September 6, 2007
- **Primary specialty:** Emergency Medicine · taxonomy 207P00000X
- **State license:** 045768 (Connecticut)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 21 ELM STREET, New Milford, CT 06776
- **Phone:** (860) 350-7222
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** 4 organizations under Medicare reassignment (form CMS-855R): The Charlotte Hungerford Hospital (NPI 1629075734, Torrington, CT); Norwalk Hospital Association (NPI 1427041581, Norwalk, CT); Hartford Healthcare Urgent Care Centers, LLC (NPI 1093239683, Avon, CT); The Hospital Of Central Connecticut At New Britain General And Bradley (NPI 1053477075, New Britain, CT) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** August 8, 2025
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Source: [NPI Profile](https://npiprofile.com/npi/1366637084) · Data from the CMS NPPES public registry.