DR. OLIVIA MASLON SIWOSKI M.D.
NPI 1609260884
Internal Medicine in Kalamazoo, MI
About Dr. Olivia Maslon Siwoski M.d. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. OLIVIA MASLON SIWOSKI M.D. (NPI 1609260884) is an individual internal medicine provider in Kalamazoo, Michigan, licensed in Michigan (4301503659) and active in the NPI registry since March 2015. She is enrolled in Medicare PECOS, is affiliated with Bronson Methodist Hospital, and maintains a secondary practice location in South Haven.
NPPES Registry Identity
Specialties & Licenses
Other Names 1
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
Dr. Olivia Maslon Siwoski M.d. 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 Olivia Siwoski reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Kalamazoo, MI 49007
- Reassigned Medicare billing, Michigan enrollment
- 1,133 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 4
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.
Bronson Methodist Hospital
Acute Care Hospitals · Kalamazoo, MIPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 49007 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.
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.
KALAMAZOO, MI 49007
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 Olivia Siwoski's NPI number?
The NPI number for Olivia Siwoski is 1609260884. It was assigned to this individual provider in the NPPES registry on March 25, 2015. The provider is also known as Dr. Olivia Anna Maslon M.D..
Where is Olivia Siwoski located?
Olivia Siwoski practices at 601 John St, Kalamazoo, MI 49007. The listed phone number is (269) 341-8481.
What is Olivia Siwoski's specialty?
The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.
Is Olivia Siwoski enrolled in Medicare?
Yes. Olivia Siwoski 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 Olivia Siwoski's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Olivia Siwoski reassigns Medicare benefits to Bronson Methodist Hospital (Kalamazoo, MI). 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 Olivia Siwoski's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Olivia Siwoski accept?
Health plans from Priority Health list Olivia Siwoski 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 Olivia Siwoski affiliated with any hospitals?
According to CMS data, Olivia Siwoski is affiliated with Bronson Methodist Hospital.
When was this NPI record last updated?
The NPPES record for Olivia Siwoski was last updated on December 7, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.
# Dr. Olivia Maslon Siwoski, M.D. · NPI 1609260884
Internal Medicine physician in Kalamazoo, Michigan. Individual provider, active in the CMS NPPES registry since March 25, 2015.
## Identity
- **NPI:** 1609260884 (Entity type: Individual)
- **Enumerated:** March 25, 2015
- **Primary specialty:** Internal Medicine · taxonomy 207R00000X
- **State license:** 4301503659 (Michigan)
- **Sole proprietor:** No
## Practice location
- **Address:** 601 JOHN ST, Kalamazoo, MI 49007-5341
- **Phone:** (269) 341-8481
## 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:** Bronson Methodist Hospital (NPI 1417961137, Kalamazoo, MI), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2015
## Record status
- **NPPES last updated:** December 7, 2021
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Source: [NPI Profile](https://npiprofile.com/npi/1609260884) · Data from the CMS NPPES public registry.