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Recently Updated NPI Information — some details in this NPI profile have been updated in the NPI registry within the last 60 days.

KATHERINE MANASSON MD INC
NPI 1356392575
Internal Medicine in Laguna Hills, CA

Active since May 12, 2006
24422 AVENIDA DE LA CARLOTA STE 272, LAGUNA HILLS, CA 92653(949) 446-6783(949) 446-9709 Get Directions Write a Review

NPPES record last updated: October 12, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Katherine Manasson Md Inc NPPES

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

KATHERINE MANASSON MD INC (NPI 1356392575) is a healthcare organization registered as an internal medicine in Laguna Hills, California and active in the NPI registry since May 2006. The organization lists Katherine Manasson, President, as its authorized official.

NPPES Registry Identity

NPI1356392575
Entity TypeOrganization
Primary Taxonomy207R00000X
Legal Business NameKATHERINE MANASSON MD INC
Location Address24422 AVENIDA DE LA CARLOTA STE 272Laguna Hills, CA 92653-3648
Mailing Address54 Coral LkIrvine, CA 92614-5443 · (949) 751-7604 · Fax (949) 348-1087
Phone(949) 446-6783
Fax(949) 446-9709
Organization SubpartNo
Authorized OfficialKatherine ManassonPresident · (949) 751-7604
Enumeration DateMay 12, 2006
Last NPPES UpdateOctober 12, 2026
NPPES CertifiedOctober 12, 2026
✔ NPI 1356392575 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207R00000X
License✔ Licensed in CA · A61594
Definition
A physician who provides long-term, comprehensive care in the office and the hospital, managing both common and complex illness of adolescents, adults and the elderly. Internists are trained in the diagnosis and treatment of cancer, infections and diseases affecting the heart, blood, kidneys, joints and digestive, respiratory and vascular systems. They are also trained in the essentials of primary care internal medicine, which incorporates an understanding of disease prevention, wellness, substance abuse, mental health and effective treatment of common problems of the eyes, ears, skin, nervous system and reproductive organs.
24422 AVENIDA DE LA CARLOTA STE 272, Laguna Hills, CA 92653
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Other Identifiers 2

Medicaid00A615940CA
OtherW19900CA · Medicare Ptan

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)

Katherine Manasson Md Inc is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Medicare Revalidation Due Date

Revalidation due by November 30, 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 IDO20060821000264Non-DME Part B · Clinic/Group PracticeDue dateNovember 30, 2026
Source: CMS Revalidation Due Date List, October 2026 release.

Clinicians Billing Medicare Through This Organization

Medicare enrollment records show 1 clinician reassigns Medicare billing to Katherine Manasson MD Inc, which bills Medicare for the services this clinician delivers.

Clinician (1)

Katherine Manasson, M.D.
Internal Medicine
NPI 1538178611
26732 CROWN VALLEY PKWY SUITE 507
Mission Viejo, CA 92691
(949) 348-1085
✔ PECOS✔ Accepts Medicare2.1 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 Katherine Manasson MD Inc's NPI number?

The NPI number for Katherine Manasson MD Inc is 1356392575. It was assigned to this organization in the NPPES registry on May 12, 2006.

Where is Katherine Manasson MD Inc located?

Katherine Manasson MD Inc is located at 24422 Avenida De La Carlota Ste 272, Laguna Hills, CA 92653. The listed phone number is (949) 446-6783.

What is Katherine Manasson MD Inc's specialty?

The primary specialty registered for this NPI is Internal Medicine with taxonomy code 207R00000X.

Is Katherine Manasson MD Inc enrolled in Medicare?

Yes. Katherine Manasson MD Inc is registered in the Medicare PECOS enrollment system.

When is Katherine Manasson MD 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 November 30, 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 Katherine Manasson MD Inc?

According to the CMS Revalidation Reassignment List (October 2026 release), 1 clinician (Internal Medicine) reassigns their Medicare billing to Katherine Manasson MD 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 Katherine Manasson MD Inc was last updated on October 12, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 12 days 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.