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GRACE LOZINSKI M.D.
NPI 1659399582
Internal Medicine in Irvine, CA

Active since July 18, 2006PECOS EnrolledAccepts Medicare Assignment
4950 BARRANCA PKWY STE 207, IRVINE, CA 92604(949) 262-9700(949) 262-0700 Get Directions Write a Review

NPPES record last updated: June 8, 2026. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Mar 3, 2026, Jul 21, 2022, Jul 28, 2017 and 1 more (4 updates tracked since 2015).

About Grace Lozinski M.d. NPPES

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

GRACE LOZINSKI M.D. (NPI 1659399582) is an individual internal medicine provider in Irvine, California, licensed in California (A77966) and active in the NPI registry since July 2006. She is enrolled in Medicare PECOS and is a graduate of New York Medical College (2000).

NPPES Registry Identity

NPI1659399582
Entity TypeIndividualFemale
Primary Taxonomy207R00000X
Provider Legal NameGRACE LOZINSKICredential: M.D.
Location Address4950 BARRANCA PKWY STE 207Irvine, CA 92604-8648
Mailing Address5000 Birch St Ste 4700Newport Beach, CA 92660-2187
Phone(949) 262-9700
Fax(949) 262-0700
Sole ProprietorNo
Medical School CMSNew York Medical CollegeGraduated 2000
Enumeration DateJuly 18, 2006
Last NPPES UpdateJune 8, 20264 updates tracked since enumeration
NPPES CertifiedJune 8, 2026
✔ NPI 1659399582 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 · A77966
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.
4950 BARRANCA PKWY STE 207, Irvine, CA 92604
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Other Identifiers 1

OtherP00048999CA · Medicare Railroad

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

Grace Lozinski 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 ID5092858399
PECOS Enrollment IDI20260128002111
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

2

Medicare enrollment records show Grace Lozinski reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Grace Lozinski MD Inc
Same address
Internal Medicine
4950 BARRANCA PKWY STE 207
Irvine, CA 92604
  • Reassigned Medicare billing, California enrollment
NPI 1811865892 (949) 262-9700
Pacific Hospitalist Associates A Medical Corporation
1.6 mi
Hospitalist
16300 SAND CANYON AVE STE 400
Irvine, CA 92618
  • Reassigned Medicare billing, California enrollment
  • 105 clinicians in this Medicare group
NPI 1912330432 (949) 610-7245

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 92604 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
$142.39 typical visit price
range $62.96 – $187.60
Typical copayment $35.59 (range $15.74 – $46.90)
Most-billed visit code 99204
Established Patient
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
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 2

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

DR. ANN LAN MAI MD
Internal Medicine
4950 BARRANCA PKWY STE 207
IRVINE, CA 92604
Orange County (949) 262-9700
GRACE LOZINSKI MD INC
Internal Medicine
4950 BARRANCA PKWY STE 207
IRVINE, CA 92604
Orange County (949) 262-9700

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 Grace Lozinski's NPI number?

The NPI number for Grace Lozinski is 1659399582. It was assigned to this individual provider in the NPPES registry on July 18, 2006.

Where is Grace Lozinski located?

Grace Lozinski practices at 4950 Barranca Pkwy Ste 207, Irvine, CA 92604. The listed phone number is (949) 262-9700.

What is Grace Lozinski's specialty?

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

Is Grace Lozinski enrolled in Medicare?

Yes. Grace Lozinski 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 organizations bill Medicare for Grace Lozinski's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Grace Lozinski reassigns Medicare benefits to 2 organizations: Grace Lozinski MD Inc (Irvine, CA) and Pacific Hospitalist Associates A Medical Corporation (Irvine, 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 Grace Lozinski'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 Grace Lozinski was last updated on June 8, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 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.