DR. WILLIAM WEN-LONG YANG MD
NPI 1790979011
Ophthalmology in Springfield, IL
About Dr. William Wen-long Yang Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. WILLIAM WEN-LONG YANG MD (NPI 1790979011) is an individual ophthalmology provider in Springfield, Illinois, licensed in Illinois (036126329) and active in the NPI registry since August 2007. He is enrolled in Medicare PECOS, is affiliated with St Johns Hospital, and maintains a secondary practice location in Walla Walla.
NPPES Registry Identity
Specialties & Licenses
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. William Wen-long Yang 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 Reassignments
2Medicare enrollment records show William Yang reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Springfield, IL 62704
- Reassigned Medicare billing, Illinois enrollment
- 21 clinicians in this Medicare group
Walla Walla, WA 99362
- Reassigned Medicare billing, Washington enrollment
- 4 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 8
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 2
Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.
St Johns Hospital
Acute Care Hospitals · Springfield, ILProvidence St Mary Medical Center
Acute Care Hospitals · Walla Walla, WAPhysician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 62704 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.
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 William Yang's NPI number?
The NPI number for William Yang is 1790979011. It was assigned to this individual provider in the NPPES registry on August 29, 2007.
Where is William Yang located?
William Yang practices at 2020 W Iles Ave, Springfield, IL 62704. The listed phone number is (217) 698-3030.
What is William Yang's specialty?
The primary specialty registered for this NPI is Ophthalmology with taxonomy code 207W00000X.
Is William Yang enrolled in Medicare?
Yes. William Yang 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 William Yang's services?
According to the CMS Revalidation Reassignment List (October 2026 release), William Yang reassigns Medicare benefits to 2 organizations: Prairie Eye Center, Ltd (Springfield, IL) and Andrew S Edwards MD PC (Walla Walla, WA). 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 William Yang's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
What insurance does William Yang accept?
Health plans from Moda Health Plan, Inc., Premera Blue Cross Blue Shield of Alaska and Providence Health Plan list William Yang 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 William Yang affiliated with any hospitals?
According to CMS data, William Yang is affiliated with St Johns Hospital and Providence St Mary Medical Center.
When was this NPI record last updated?
The NPPES record for William Yang was last updated on February 22, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 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. William Wen-Long Yang, MD · NPI 1790979011
Ophthalmology physician in Springfield, Illinois. Individual provider, active in the CMS NPPES registry since August 29, 2007.
## Identity
- **NPI:** 1790979011 (Entity type: Individual)
- **Enumerated:** August 29, 2007
- **Primary specialty:** Ophthalmology · taxonomy 207W00000X
- **State license:** 036126329 (Illinois)
- **Sole proprietor:** No
## Practice location
- **Address:** 2020 W ILES AVE, Springfield, IL 62704-7015
- **Phone:** (217) 698-3030 · **Fax:** (217) 698-4729
## 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): Prairie Eye Center, Ltd (NPI 1447222864, Springfield, IL); Andrew S Edwards MD PC (NPI 1083076624, Walla Walla, WA) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** University Of Wisconsin School Of Medicine, class of 2004
## Record status
- **NPPES last updated:** February 22, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1790979011) · Data from the CMS NPPES public registry.