DR. TIMMOTHY O MERRIGAN M.D.
NPI 1063442945
Family Medicine in Walnut Creek, CA
About Dr. Timmothy O Merrigan M.d. NPPES
Official registry information on file with the National Plan and Provider Enumeration System.
DR. TIMMOTHY O MERRIGAN M.D. (NPI 1063442945) is an individual family medicine provider in Walnut Creek, California, licensed in California (A63055) and active in the NPI registry since July 2006. He is enrolled in Medicare PECOS and is a graduate of Medical College Of Wisconsin (1995).
NPPES Registry Identity
Specialties & Licenses
Other Identifiers 1
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. Timmothy O Merrigan 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 Timmothy Merrigan reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.
Richmond, CA 94801
- Reassigned Medicare billing, California enrollment
- 20,078 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 94598 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.
WALNUT CREEK, CA 94598
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 Timmothy Merrigan's NPI number?
The NPI number for Timmothy Merrigan is 1063442945. It was assigned to this individual provider in the NPPES registry on July 4, 2006.
Where is Timmothy Merrigan located?
Timmothy Merrigan practices at 320 Lennon Ln, Walnut Creek, CA 94598. The listed phone number is (924) 906-2326.
What is Timmothy Merrigan's specialty?
The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.
Is Timmothy Merrigan enrolled in Medicare?
Yes. Timmothy Merrigan 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 Timmothy Merrigan's services?
According to the CMS Revalidation Reassignment List (October 2026 release), Timmothy Merrigan reassigns Medicare benefits to Permanente Medical Group Inc (Richmond, CA). 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 Timmothy Merrigan'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 Timmothy Merrigan was last updated on February 11, 2022. 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. Timmothy O Merrigan, M.D. · NPI 1063442945
Family Medicine physician in Walnut Creek, California. Individual provider, active in the CMS NPPES registry since July 4, 2006.
## Identity
- **NPI:** 1063442945 (Entity type: Individual)
- **Enumerated:** July 4, 2006
- **Primary specialty:** Family Medicine · taxonomy 207Q00000X
- **State license:** A63055 (California)
- **Sole proprietor:** Yes
## Practice location
- **Address:** 320 LENNON LN, Walnut Creek, CA 94598-2419
- **Phone:** (924) 906-2326
## 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:** Permanente Medical Group Inc (NPI 1235226531, Richmond, CA), under Medicare reassignment (form CMS-855R) · CMS Revalidation Reassignment List, October 2026 release
- **Medical school:** Medical College Of Wisconsin, class of 1995
## Record status
- **NPPES last updated:** February 11, 2022
- **Other identifiers:** Medicaid 00A630550 (CA)
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Source: [NPI Profile](https://npiprofile.com/npi/1063442945) · Data from the CMS NPPES public registry.