Doctor profile · Federal record

Dr. Diana Williams, FNP

Family Nurse Practitioner (CMS: Nurse Practitioner) · Los Alamitos, CA

  • NPI 1174025886
  • Accepts Medicare
  • 9 yrs in practice
  • Female
  • Group practice
  • No sanctions

Practice & contact

Operates at 3 locations .

NPPES Updated May 11, 2026
Primary practice
4288 Katella Ave
Los Alamitos, CA 907203562
(562) 256-8514
fax (562) 296-8561
Additional location
123 Atlantic Ave
Long Beach, CA 908025121
(562) 726-1383
Additional location
4237 Atlantic Ave
Long Beach, CA 908072801
(562) 336-1656
Mailing address
12923 Lefloss Ave
Norwalk, CA 906502548

Credentials & registration

NPPES · NUCC
NPI registered
March 2018 — 8 yrs on file
Profile last updated
April 5, 2018
Year of graduation
2017 — 9 yrs since
Specialty taxonomy
363LF0000X — NUCC code
State license (1)
California #95008594

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1174025886. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
17
Distinct HCPCS
1
Medicare allowed
$1,423
HCPCS Description Services Patients Avg allowed
99213 Established patient office or other outpatient visit, 20-29 minutes 17 17 $84

In context: peer comparison

Among 2 peers in Los Alamitos Family Nurse Practitioner, average services per provider: 31. This provider delivers 0.5× the peer median.

Frequently asked questions

Auto-generated from federal data
What is Dr. Diana Williams's medical specialty?
Dr. Diana Williams practices Family Nurse Practitioner in Los Alamitos, CA.
Where does Dr. Diana Williams practice?
Dr. Diana Williams practices at 4288 Katella Ave, Los Alamitos, CA 907203562. Office phone: 5622568514.
What is Dr. Diana Williams's NPI?
Dr. Diana Williams's National Provider Identifier (NPI) is 1174025886, issued by NPPES.
Does Dr. Diana Williams accept Medicare assignment?
Yes. Dr. Diana Williams accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Diana Williams commonly perform?
Top Medicare-reported procedures in 2023: Established patient office or other outpatient visit (HCPCS 99213). Source: CMS Medicare Physician & Other Practitioners file.