XIU YING AU
NPI 1659923712
Internal Medicine - Endocrinology, Diabetes & Metabolism in Billings, MT
About Xiu Ying Au NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
XIU YING AU (NPI 1659923712) is an individual endocrinology, diabetes & metabolism provider in Billings, Montana, licensed in Montana (130241) and active in the NPI registry since July 2019. She is enrolled in Medicare PECOS, is affiliated with Billings Clinic, and maintains 2 additional practice locations.
NPPES Registry Identity
Specialties & Licenses 2
Secondary Practice Locations 2
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
Xiu Ying Au 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 Xiu Ying Au reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Billings, MT 59101
- Reassigned Medicare billing, Montana enrollment
- 1,264 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 5
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
Billings Clinic
Acute Care Hospitals · Billings, MTBeartooth Billings Clinic
Critical Access Hospitals · Red Lodge, MTCentral Montana Medical Center
Critical Access Hospitals · Lewistown, MTSheridan Memorial Hospital
Acute Care Hospitals · Sheridan, WYPowell Valley Hospital
Critical Access Hospitals · Powell, WYPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 59101 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 17
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
BILLINGS, MT 59101
BILLINGS, MT 59101
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 Xiu Ying Au's NPI number?
The NPI number for Xiu Ying Au is 1659923712. It was assigned to this individual provider in the NPPES registry on July 9, 2019.
Where is Xiu Ying Au located?
Xiu Ying Au practices at 1045 N 30th St, Billings, MT 59101. The listed phone number is (406) 238-2500.
What is Xiu Ying Au's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Endocrinology, Diabetes & Metabolism, with taxonomy code 207RE0101X.
Is Xiu Ying Au enrolled in Medicare?
Yes. Xiu Ying Au 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 Xiu Ying Au's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Xiu Ying Au reassigns Medicare benefits to Billings Clinic (Billings, MT). 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 Xiu Ying Au's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does Xiu Ying Au accept?
Health plans from Blue Cross and Blue Shield of Montana, Mountain Health CO-OP, PacificSource Health Plans and Providence Health Plan list Xiu Ying Au 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 Xiu Ying Au affiliated with any hospitals?
According to CMS data, Xiu Ying Au is affiliated with Billings Clinic, Beartooth Billings Clinic, Central Montana Medical Center, Sheridan Memorial Hospital and Powell Valley Hospital.
When was this NPI record last updated?
The NPPES record for Xiu Ying Au was last updated on June 20, 2024. 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.
# Xiu Ying Au · NPI 1659923712
Endocrinology, Diabetes & Metabolism physician in Billings, Montana. Individual provider, active in the CMS NPPES registry since July 9, 2019.
## Identity
- **NPI:** 1659923712 (Entity type: Individual)
- **Enumerated:** July 9, 2019
- **Primary specialty:** Internal Medicine - Endocrinology, Diabetes & Metabolism · taxonomy 207RE0101X
- **State license:** 130241 (Montana)
- **Sole proprietor:** No
## Practice location
- **Address:** 1045 N 30TH ST, Billings, MT 59101-0733
- **Phone:** (406) 238-2500
## 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:** Billings Clinic (NPI 1013957000, Billings, MT), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Other, class of 2014
## Record status
- **NPPES last updated:** June 20, 2024
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Source: [NPI Profile](https://npiprofile.com/npi/1659923712) · Data from the CMS NPPES public registry.