JOHN MELLAS MD
NPI 1497712079
Internal Medicine - Nephrology in Fenton, MO
About John Mellas Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
JOHN MELLAS MD (NPI 1497712079) is an individual nephrology provider in Fenton, Missouri, licensed in Missouri (R3E73) and active in the NPI registry since April 2006. He is enrolled in Medicare PECOS, is affiliated with Northwestern Medicine Central Dupage Hospital, and maintains a secondary practice location in Saint Louis.
NPPES Registry Identity
Specialties & Licenses
Secondary Practice Location 1
Other Identifiers 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
John Mellas 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 Reassignment
Medicare enrollment records show John Mellas reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Fenton, MO 63026
- Reassigned Medicare billing, Missouri enrollment
- Also billed through NPI 1770554842 (Missouri)
- 2 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 6
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 4
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Northwestern Medicine Central Dupage Hospital
Acute Care Hospitals · Winfield, ILSsm St Clare Health Center
Acute Care Hospitals · Fenton, MOSsm Health St Mary's Hospital - St Louis
Acute Care Hospitals · Richmond Heights, MOMissouri Baptist Medical Center
Acute Care Hospitals · Town And Country, MOPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 63026 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.
FENTON, MO 63026
FENTON, MO 63026
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 John Mellas's NPI number?
The NPI number for John Mellas is 1497712079. It was assigned to this individual provider in the NPPES registry on April 27, 2006.
Where is John Mellas located?
John Mellas practices at 1011 Bowles Ave Ste 220, Fenton, MO 63026. The listed phone number is (636) 681-3030.
What is John Mellas's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Nephrology, with taxonomy code 207RN0300X.
Is John Mellas enrolled in Medicare?
Yes. John Mellas 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 organization bills Medicare for John Mellas's services?
According to the CMS Revalidation Reassignment List (October 2026 release), John Mellas reassigns Medicare benefits to Nephrology And Hypertension Specialists, LLC (Fenton, MO). The 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 John Mellas's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does John Mellas accept?
Health plans from Anthem Blue Cross and Blue Shield, Medica, Oscar Insurance Company and UnitedHealthcare list John Mellas 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 John Mellas affiliated with any hospitals?
According to CMS data, John Mellas is affiliated with Northwestern Medicine Central Dupage Hospital, Ssm St Clare Health Center, Ssm Health St Mary's Hospital - St Louis and Missouri Baptist Medical Center.
When was this NPI record last updated?
The NPPES record for John Mellas was last updated on December 20, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 2 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.
# John Mellas, MD · NPI 1497712079
Nephrology physician in Fenton, Missouri. Individual provider, active in the CMS NPPES registry since April 27, 2006.
## Identity
- **NPI:** 1497712079 (Entity type: Individual)
- **Enumerated:** April 27, 2006
- **Primary specialty:** Internal Medicine - Nephrology · taxonomy 207RN0300X
- **State license:** R3E73 (Missouri)
- **Sole proprietor:** No
## Practice location
- **Address:** 1011 BOWLES AVE STE 220, Fenton, MO 63026-2384
- **Phone:** (636) 681-3030 · **Fax:** (636) 326-1545
## 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:** Nephrology And Hypertension Specialists, LLC (NPI 1730127200, Fenton, MO), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Illinois College Of Med, class of 1977
## Record status
- **NPPES last updated:** December 20, 2023
- **Other identifiers:** Medicaid 202250106 (MO)
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Source: [NPI Profile](https://npiprofile.com/npi/1497712079) · Data from the CMS NPPES public registry.