TIMOTHY M SOWERBY MD
NPI 1063475952
Internal Medicine - Gastroenterology in Petaluma, CA
About Timothy M Sowerby Md NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
TIMOTHY M SOWERBY MD (NPI 1063475952) is an individual gastroenterology provider in Petaluma, California, licensed in California (A50116) and active in the NPI registry since April 2006. He is enrolled in Medicare PECOS.
NPPES Registry Identity
Specialties & Licenses
Medicare Participation & PECOS CMS
Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.
Medicare Enrollment Status
Enrolled in Medicare (PECOS)
Timothy M Sowerby Md is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).
Medicare Billing Reassignments
2Medicare enrollment records show Timothy Sowerby reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.
Vallejo, CA 94589
- Reassigned Medicare billing, California enrollment
- 20,078 clinicians in this Medicare group
San Francisco, CA 94143
- Reassigned Medicare billing, California enrollment
- 339 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 94954 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.
PETALUMA, CA 94954
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 Timothy Sowerby's NPI number?
The NPI number for Timothy Sowerby is 1063475952. It was assigned to this individual provider in the NPPES registry on April 11, 2006.
Where is Timothy Sowerby located?
Timothy Sowerby practices at 3900 Lakeville Hwy, Petaluma, CA 94954. The listed phone number is (707) 765-3900.
What is Timothy Sowerby's specialty?
The primary specialty registered for this NPI is Internal Medicine, specializing in Gastroenterology, with taxonomy code 207RG0100X.
Is Timothy Sowerby enrolled in Medicare?
Yes. Timothy Sowerby is registered in the Medicare PECOS enrollment system.
Which organizations bill Medicare for Timothy Sowerby's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Timothy Sowerby reassigns Medicare benefits to 2 organizations: Permanente Medical Group Inc (Vallejo, CA) and Regents Univ Of California Ucsf (San Francisco, CA). 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 Timothy Sowerby'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 Timothy Sowerby was last updated on January 15, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 9 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.
# Timothy M Sowerby, MD · NPI 1063475952
Gastroenterology physician in Petaluma, California. Individual provider, active in the CMS NPPES registry since April 11, 2006.
## Identity
- **NPI:** 1063475952 (Entity type: Individual)
- **Enumerated:** April 11, 2006
- **Primary specialty:** Internal Medicine - Gastroenterology · taxonomy 207RG0100X
- **State license:** A50116 (California)
- **Sole proprietor:** No
## Practice location
- **Address:** 3900 LAKEVILLE HWY, Petaluma, CA 94954-5698
- **Phone:** (707) 765-3900
## 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:** 2 organizations under Medicare reassignment (form CMS-855R): Permanente Medical Group Inc (NPI 1336222397, Vallejo, CA); Regents Univ Of California Ucsf (NPI 1124439807, San Francisco, CA) · CMS Revalidation Reassignment List, October 2026 release
## Record status
- **NPPES last updated:** January 15, 2026
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Source: [NPI Profile](https://npiprofile.com/npi/1063475952) · Data from the CMS NPPES public registry.