STEVEN MACHTINGER MD & ASSOCIATES INC
NPI 1427288133
Allergy & Immunology in San Mateo, CA

Q: What is Steven Machtinger MD & Associates Inc's specialty?

The primary specialty registered for this NPI is Allergy & Immunology with taxonomy code 207K00000X.

Active since July 16, 2009

100 S ELLSWORTH AVE, SUITE 700, SAN MATEO, CA 94401(650) 696-8230(650) 696-8238 Get Directions Write a Review

NPPES record last updated: April 20, 2023. Verified against the NPPES registry weekly; last sync: October 18, 2026.

On this page

About Steven Machtinger Md & Associates Inc NPPES

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

STEVEN MACHTINGER MD & ASSOCIATES INC (NPI 1427288133) is a healthcare organization registered as an allergy & immunology in San Mateo, California and active in the NPI registry since July 2009. The organization lists Steven B Machtinger Md, Owner Physician President, as its authorized official.

NPPES Registry Identity

NPI1427288133

Entity TypeOrganization

Primary Taxonomy207K00000X

Legal Business NameSTEVEN MACHTINGER MD & ASSOCIATES INC

Location Address100 S ELLSWORTH AVE, SUITE 700San Mateo, CA 94401-3939

Mailing Address100 S Ellsworth Ave, Suite 700San Mateo, CA 94401-3939 · (650) 696-8230 · Fax (650) 696-8238

Phone(650) 696-8230

Fax(650) 696-8238

Organization SubpartNo

Authorized OfficialSteven B Machtinger MdOwner Physician President · (650) 696-8230

Enumeration DateJuly 16, 2009

Last NPPES UpdateApril 20, 2023

NPPES CertifiedApril 20, 2023

✔ NPI 1427288133 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyAllergy & ImmunologyAllopathic & Osteopathic Physicians

Taxonomy Code207K00000X

Definition

An allergist-immunologist is trained in evaluation, physical and laboratory diagnosis, and management of disorders involving the immune system. Selected examples of such conditions include asthma, anaphylaxis, rhinitis, eczema, and adverse reactions to drugs, foods, and insect stings as well as immune deficiency diseases (both acquired and congenital), defects in host defense, and problems related to autoimmune disease, organ transplantation, or malignancies of the immune system.

100 S ELLSWORTH AVE, San Mateo, CA 94401

Open in Google Maps ↗

Group Practice 1

Group TaxonomyThis provdier is a business group of one or more individual practitioners, all of who practice with the same area of specialization.193400000X SINGLE SPECIALTY GROUP

Medicare Participation & PECOS CMS

Medicare enrollment, revalidation and the clinicians who bill Medicare through this organization, from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Steven Machtinger Md & Associates Inc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Medicare Revalidation Due Date

Revalidation due by October 31, 2026

Medicare-enrolled providers and suppliers confirm their enrollment information with CMS on a set cycle, every 5 years for most and every 3 years for medical equipment suppliers. CMS sets the due date for each enrollment.

StateEnrollment IDDue date

StateCaliforniaEnrollment IDO20121210000073Non-DME Part B · Clinic/Group PracticeDue dateOctober 31, 2026

Source: CMS Revalidation Due Date List, October 2026 release.

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 2 clinicians reassign Medicare billing to Steven Machtinger MD & Associates Inc, which bills Medicare for the services they deliver. They are listed nearest first.

Clinicians, nearest first (2)

Dean Kardassakis, MD

Allergy/Immunology

NPI 1811906571

450 SUTTER ST RM 933
San Francisco, CA 94108

(415) 362-5443

✔ PECOS✔ Accepts Medicare16 mi

Steven Machtinger, MD

Allergy/Immunology

NPI 1093719437

450 SUTTER ST RM 933
San Francisco, CA 94108

(415) 362-5443

✔ PECOS✔ Accepts Medicare16 mi

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

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 Steven Machtinger MD & Associates Inc's NPI number?

The NPI number for Steven Machtinger MD & Associates Inc is 1427288133. It was assigned to this organization in the NPPES registry on July 16, 2009.

Where is Steven Machtinger MD & Associates Inc located?

Steven Machtinger MD & Associates Inc is located at 100 S Ellsworth Ave Suite 700, San Mateo, CA 94401. The listed phone number is (650) 696-8230.

What is Steven Machtinger MD & Associates Inc's specialty?

The primary specialty registered for this NPI is Allergy & Immunology with taxonomy code 207K00000X.

Is Steven Machtinger MD & Associates Inc enrolled in Medicare?

Yes. Steven Machtinger MD & Associates Inc is registered in the Medicare PECOS enrollment system.

When is Steven Machtinger MD & Associates Inc's Medicare revalidation due?

According to the CMS Revalidation Due Date List (October 2026 release), the Medicare Non-DME Part B enrollment for this organization (California, Clinic/Group Practice) is due for revalidation by October 31, 2026. Medicare providers and suppliers revalidate their enrollment every 5 years, and medical equipment suppliers every 3 years. Confirm current requirements with your Medicare Administrative Contractor.

How many clinicians bill Medicare through Steven Machtinger MD & Associates Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 2 clinicians, all in Allergy/Immunology, reassign their Medicare billing to Steven Machtinger MD & Associates Inc. A 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 the clinician's services. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

When was this NPI record last updated?

The NPPES record for Steven Machtinger MD & Associates Inc was last updated on April 20, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 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.