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DR. LAWRENCE JAMES WILLIAMSON M.D.
NPI 1508821273
Family Medicine in Windsor, CA

Active since April 18, 2006PECOS EnrolledAccepts Medicare Assignment
911 MEDICAL CENTER PLAZA, SUITE 23, WINDSOR, CA 95492(707) 837-0170(707) 837-0177 Get Directions Write a Review

NPPES record last updated: May 4, 2010. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. Lawrence James Williamson M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. LAWRENCE JAMES WILLIAMSON M.D. (NPI 1508821273) is an individual family medicine provider in Windsor, California, licensed in California (A73495) and active in the NPI registry since April 2006. He is enrolled in Medicare PECOS and is a graduate of Other (1997).

NPPES Registry Identity

NPI1508821273
Entity TypeIndividualMale
Primary Taxonomy207Q00000X
Provider Legal NameDR. LAWRENCE JAMES WILLIAMSONCredential: M.D.
Location Address911 MEDICAL CENTER PLAZA, SUITE 23Windsor, CA 95492-7817
Mailing AddressPo Box 1820Windsor, CA 95492-1820 · (707) 837-0170 · Fax (707) 837-0177
Phone(707) 837-0170
Fax(707) 837-0177
Sole ProprietorNo
Medical School CMSOtherGraduated 1997
Enumeration DateApril 18, 2006
Last NPPES UpdateMay 4, 2010
✔ NPI 1508821273 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
License✔ Licensed in CA · A73495
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
911 MEDICAL CENTER PLAZA, Windsor, CA 95492
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Other Identifiers 1

Medicare UPINH39456

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. Lawrence James Williamson 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.

PECOS PAC ID9335032465
PECOS Enrollment IDI20040203001121
Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignment

Medicare enrollment records show Lawrence Williamson reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Department Of State Hospitals
35 mi
Psychiatric Hospital
2100 NAPA VALLEJO HWY
Napa, CA 94558
  • Reassigned Medicare billing, California enrollment
  • 755 clinicians in this Medicare group
NPI 1326098161 (707) 253-5000

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 95492 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$96.16 typical visit price
range $63.04 – $187.01
Typical copayment $24.04 (range $15.76 – $46.75)
Most-billed visit code 99203
Established Patient
$109.88 typical visit price
range $21.02 – $153.40
Typical copayment $27.47 (range $5.25 – $38.35)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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 Lawrence Williamson's NPI number?

The NPI number for Lawrence Williamson is 1508821273. It was assigned to this individual provider in the NPPES registry on April 18, 2006.

Where is Lawrence Williamson located?

Lawrence Williamson practices at 911 Medical Center Plaza Suite 23, Windsor, CA 95492. The listed phone number is (707) 837-0170.

What is Lawrence Williamson's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is Lawrence Williamson enrolled in Medicare?

Yes. Lawrence Williamson 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 Lawrence Williamson's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Lawrence Williamson reassigns Medicare benefits to Department Of State Hospitals (Napa, 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 Lawrence Williamson'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 Lawrence Williamson was last updated on May 4, 2010. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.