MARGARET SIU
NPI 1427518455
Surgery in Springfield, MA
About Margaret Siu NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
MARGARET SIU (NPI 1427518455) is an individual surgery provider in Springfield, Massachusetts, licensed in Maryland (D0104111) and active in the NPI registry since March 2019. She is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses 2
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Margaret Siu is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignment
Medicare enrollment records show Margaret Siu reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Baltimore, MD 21201
- Reassigned Medicare billing, Maryland enrollment
- Medicare enrollment name: Shock Trauma Associates PA
- 541 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.
Physician Visit Costs CMS claims · ZIP area
Typical Medicare office-visit costs in the 01199 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 20
Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.
SPRINGFIELD, MA 01199
SPRINGFIELD, MA 01199
SPRINGFIELD, MA 01199
SPRINGFIELD, MA 01199
SPRINGFIELD, MA 01199
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 Margaret Siu's NPI number?
The NPI number for Margaret Siu is 1427518455. It was assigned to this individual provider in the NPPES registry on March 25, 2019.
Where is Margaret Siu located?
Margaret Siu practices at 759 Chestnut St, Springfield, MA 01199. The listed phone number is (413) 794-0000.
What is Margaret Siu's specialty?
The primary specialty registered for this NPI is Surgery with taxonomy code 208600000X.
Is Margaret Siu enrolled in Medicare?
Yes. Margaret Siu is registered in the Medicare PECOS enrollment system.
Which organization bills Medicare for Margaret Siu's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Margaret Siu reassigns Medicare benefits to Shock Trauma Associates, P.A. (Baltimore, MD). 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 Margaret Siu's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.
When was this NPI record last updated?
The NPPES record for Margaret Siu was last updated on June 2, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.
# Margaret Siu · NPI 1427518455
Surgery physician in Springfield, Massachusetts. Individual provider, active in the CMS NPPES registry since March 25, 2019.
## Identity
- **NPI:** 1427518455 (Entity type: Individual)
- **Enumerated:** March 25, 2019
- **Primary specialty:** Surgery · taxonomy 208600000X
- **State license:** D0104111 (Maryland)
- **Sole proprietor:** No
## Practice location
- **Address:** 759 CHESTNUT ST, Springfield, MA 01199-0001
- **Phone:** (413) 794-0000
## Medicare
- **Medicare:** Enrolled in Medicare (PECOS)
- **Ordering & referring:** eligible for Part B labs & imaging, durable medical equipment, home health, power mobility devices
- **Bills Medicare through:** Shock Trauma Associates, P.A. (NPI 1679512909, Baltimore, MD), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** June 2, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1427518455) · Data from the CMS NPPES public registry.