PROF. DIANA EMERSON N.P
NPI 1194836494
Nurse Practitioner in San Mateo, CA

Q: What is Diana Emerson's NPI number?

The NPI number for Diana Emerson is 1194836494. It was assigned to this individual provider in the NPPES registry on August 31, 2006.

Q: What is Diana Emerson's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Q: When was this NPI record last updated?

The NPPES record for Diana Emerson was last updated on June 23, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.

Active since August 31, 2006PECOS Enrolled

100 S SAN MATEO DR, SAN MATEO, CA 94401(650) 404-8408 Get Directions Write a Review

NPPES record last updated: June 23, 2025. Verified against the NPPES registry weekly; last sync: November 08, 2026.

Record update history: Jun 23, 2025, Jun 22, 2020, Nov 27, 2015 (3 updates tracked since 2015).

On this page

About Prof. Diana Emerson N.p NPPES

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

PROF. DIANA EMERSON N.P (NPI 1194836494) is an individual nurse practitioner in San Mateo, California, licensed in California (NP5213) and active in the NPI registry since August 2006. She is enrolled in Medicare PECOS and maintains a secondary practice location in Sacramento.

NPPES Registry Identity

NPI1194836494

Entity TypeIndividualFemale

Primary Taxonomy363L00000X

Provider Legal NamePROF. DIANA EMERSONCredential: N.P

Location Address100 S SAN MATEO DRSan Mateo, CA 94401-3805

Mailing AddressPo Box 276950Sacramento, CA 95827-6950 · (800) 470-0071

Phone(650) 404-8408

Sole ProprietorNo

Enumeration DateAugust 31, 2006

Last NPPES UpdateJune 23, 20253 updates tracked since enumeration

NPPES CertifiedJune 23, 2025

✔ NPI 1194836494 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse PractitionerPhysician Assistants & Advanced Practice Nursing Providers

Taxonomy Code363L00000X

License✔ Licensed in CA · NP5213

Definition

(1) A registered nurse provider with a graduate degree in nursing prepared for advanced practice involving independent and interdependent decision making and direct accountability for clinical judgment across the health care continuum or in a certified specialty. (2) A registered nurse who has completed additional training beyond basic nursing education and who provides primary health care services in accordance with state nurse practice laws or statutes. Tasks performed by nurse practitioners vary with practice requirements mandated by geographic, political, economic, and social factors. Nurse practitioner specialists include, but are not limited to, family nurse practitioners, gerontological nurse practitioners, pediatric nurse practitioners, obstetric-gynecologic nurse practitioners, and school nurse practitioners.

100 S SAN MATEO DR, San Mateo, CA 94401

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Secondary Practice Location 1

Location 11625 Stockton BlvdSacramento, CA 95816-7097 · Phone (916) 262-9108 · Fax (916) 262-9109

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Prof. Diana Emerson N.p is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

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 Reassignments

Medicare enrollment records show Diana Emerson reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

San Mateo County

1.6 mi

Community/Behavioral Health

1950 ALAMEDA DE LAS PULGAS
San Mateo, CA 94403

Reassigned Medicare billing, California enrollment
Medicare enrollment name: County Of San Mateo
Also billed through NPI 1831268580 (California)
597 clinicians in this Medicare group

NPI 1710908272 (650) 573-3571

Cep America - California

3.0 mi

Emergency Medicine

222 W 39TH AVE
San Mateo, CA 94403

Reassigned Medicare billing, California enrollment
2,323 clinicians in this Medicare group

NPI 1609286400 (650) 573-2222

Sutter Valley Medical Foundation

48 mi

Multi-Specialty

2720 LOW CT
Fairfield, CA 94534

Reassigned Medicare billing, California enrollment
3,056 clinicians in this Medicare group

NPI 1184859894 (707) 428-2731

Vituity-California Observation Services PC

83 mi

Emergency Medicine

2825 CAPITOL AVE
Sacramento, CA 95816

Reassigned Medicare billing, California enrollment
73 clinicians in this Medicare group

NPI 1447148705 (916) 887-0000

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 5

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

89 services86 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.

61 services58 patients

Automated urinalysis test 81003

An automated urinalysis test is a routine examination that checks your urine for various substances. It can help identify potential health issues such as kidney problems or diabetes. The test uses a machine to analyze a small urine sample, providing quick and accurate results.

37 services34 patients

Detection test by multiplex amplified probe technique for severe acute respiratory syndrome coronavirus 2 (sars-cov-2) (covid-19), influenza virus types a and b, and respiratory syncytial virus 87637

This test identifies if you have COVID-19, influenza A or B, or respiratory syncytial virus. It uses a multiplex amplified probe technique, which amplifies and detects specific genetic material of the viruses, helping in accurate diagnosis.

17 services17 patients

Detection test by immunoassay with direct visual observation for streptococcus, group a (strep) 87880

A detection test by immunoassay for Group A Strep is a quick procedure to identify a bacterial infection in your throat. It involves taking a throat swab and applying it to a test strip, which changes color if Strep bacteria are present.

16 services16 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94401 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

$104.51 typical visit price

range $69.00 – $202.35

Typical copayment $26.12 (range $17.25 – $50.58)

Most-billed visit code 99203

Established Patient

$119.48 typical visit price

range $23.44 – $166.46

Typical copayment $29.87 (range $5.86 – $41.61)

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.

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.

HARRIET BETH BOROFSKY M.D.

Radiology (Diagnostic Radiology)

100 S SAN MATEO DR
SAN MATEO, CA 94401

San Mateo County (650) 696-4140

SUTTER BAY HOSPITALS

Psychiatric Unit

100 S SAN MATEO DR
SAN MATEO, CA 94401

San Mateo County (650) 696-5400

CLAY HUGHES NAPPER M.D.

Radiology (Diagnostic Radiology)

100 S SAN MATEO DR
SAN MATEO, CA 94401

San Mateo County (650) 696-4515

QUAN MY TRAN DO

Family Medicine

100 S SAN MATEO DR
SAN MATEO, CA 94401

San Mateo County (650) 696-4515

VALERIE NOWAKOWSKI MD

Radiology (Radiation Oncology)

100 S SAN MATEO DR
SAN MATEO, CA 94401

San Mateo County (650) 336-8117

JEFFREY J. GUTTAS. MD, INC.

Allergy & Immunology

100 S SAN MATEO DR, STE 400
SAN MATEO, CA 94401

San Mateo County (650) 696-4101

DR. JEFFREY JOHN GUTTAS M.D.

Internal Medicine (Cardiovascular Disease)

100 S SAN MATEO DR, SUITE 400
SAN MATEO, CA 94401

San Mateo County (650) 696-4100

HAIDEE SUI DPT

Physical Therapist

100 S SAN MATEO DR
SAN MATEO, CA 94401

San Mateo County (650) 696-4315

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 Diana Emerson's NPI number?

The NPI number for Diana Emerson is 1194836494. It was assigned to this individual provider in the NPPES registry on August 31, 2006.

Where is Diana Emerson located?

Diana Emerson practices at 100 S San Mateo Dr, San Mateo, CA 94401. The listed phone number is (650) 404-8408.

What is Diana Emerson's specialty?

The primary specialty registered for this NPI is Nurse Practitioner with taxonomy code 363L00000X.

Is Diana Emerson enrolled in Medicare?

Yes. Diana Emerson is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Diana Emerson's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Diana Emerson reassigns Medicare benefits to 4 organizations: San Mateo County (San Mateo, CA), Cep America - California (San Mateo, CA), Sutter Valley Medical Foundation (Fairfield, CA) and Vituity-California Observation Services PC (Sacramento, 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 Diana Emerson'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 Diana Emerson was last updated on June 23, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 16 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.