GRANT OAKLEY D.O.
NPI 1679927537
Internal Medicine - Nephrology in Portland, ME
About Grant Oakley D.o. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
GRANT OAKLEY D.O. (NPI 1679927537) is an individual nephrology provider in Portland, Maine, licensed in Maine (DO3180) and active in the NPI registry since April 2016. He is enrolled in Medicare PECOS, is affiliated with Maine Medical Center, and maintains a secondary practice location in Portland.
NPPES Registry Identity
Specialties & Licenses 2
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
Grant Oakley D.o. 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
2Medicare enrollment records show Grant Oakley reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Portland, ME 04102
- Reassigned Medicare billing, Maine enrollment
- 264 clinicians in this Medicare group
South Portland, ME 04106
- Reassigned Medicare billing, Maine enrollment
- 3,140 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 9
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.
Hospital Affiliations CMS Care Compare
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Maine Medical Center
Acute Care Hospitals · Portland, MEPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 04102 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.
Medicare Quality Performance CMS QPP · MIPS
Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.
Referred Medical Equipment & Supplies CMS DME claims 2
Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.
Other Providers at the Same Location NPPES 13
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
PORTLAND, ME 04102
PORTLAND, ME 04102
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 Grant Oakley's NPI number?
The NPI number for Grant Oakley is 1679927537. It was assigned to this individual provider in the NPPES registry on April 18, 2016.
Where is Grant Oakley located?
Grant Oakley practices at 1600 Congress St Ste B, Portland, ME 04102. The listed phone number is (207) 774-5222.
What is Grant Oakley's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.
Is Grant Oakley enrolled in Medicare?
Yes. Grant Oakley 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 Grant Oakley's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Grant Oakley reassigns Medicare benefits to 2 organizations: Maine Medical Partners (Portland, ME) and Mainehealth (South Portland, ME). 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 Grant Oakley's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Grant Oakley accept?
Health plans from Anthem Blue Cross and Blue Shield and Taro Health list Grant Oakley 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 Grant Oakley affiliated with any hospitals?
According to CMS data, Grant Oakley is affiliated with Maine Medical Center.
When was this NPI record last updated?
The NPPES record for Grant Oakley was last updated on August 3, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 years 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.
# Grant Oakley, D.O. · NPI 1679927537
Nephrology physician in Portland, Maine. Individual provider, active in the CMS NPPES registry since April 18, 2016.
## Identity
- **NPI:** 1679927537 (Entity type: Individual)
- **Enumerated:** April 18, 2016
- **Primary specialty:** Internal Medicine - Nephrology · taxonomy 207RN0300X
- **State license:** DO3180 (Maine)
- **Sole proprietor:** No
## Practice location
- **Address:** 1600 CONGRESS ST STE B, Portland, ME 04102-2148
- **Phone:** (207) 774-5222
## 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:** 2 organizations under Medicare reassignment (form CMS-855R): Maine Medical Partners (NPI 1124335591, Portland, ME); Mainehealth (NPI 1679887400, South Portland, ME) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Lake Erie College Of Osteopathic Medicine, Erie, class of 2016
## Record status
- **NPPES last updated:** August 3, 2021
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Source: [NPI Profile](https://npiprofile.com/npi/1679927537) · Data from the CMS NPPES public registry.