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DR. NICHOLAS WITHROW GRECO M.D.
NPI 1023325289
Emergency Medicine in Pasadena, CA

Active since September 09, 2010PECOS EnrolledAccepts Medicare Assignment
100 W CALIFORNIA BLVD, PASADENA, CA 91105(626) 397-5112 Get Directions Write a Review

NPPES record last updated: August 21, 2013. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Dr. Nicholas Withrow Greco M.d. NPPES

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

DR. NICHOLAS WITHROW GRECO M.D. (NPI 1023325289) is an individual emergency medicine provider in Pasadena, California, licensed in California (A113953) and active in the NPI registry since September 2010. He is enrolled in Medicare PECOS and is a graduate of Other (2009).

NPPES Registry Identity

NPI1023325289
Entity TypeIndividualMale
Primary Taxonomy207P00000X
Provider Legal NameDR. NICHOLAS WITHROW GRECOCredential: M.D.
Location Address100 W CALIFORNIA BLVDPasadena, CA 91105-3010
Mailing Address100 W California BlvdPasadena, CA 91105-3010 · (626) 397-5112
Phone(626) 397-5112
Sole ProprietorYes
Medical School CMSOtherGraduated 2009
Enumeration DateSeptember 9, 2010
Last NPPES UpdateAugust 21, 2013
✔ NPI 1023325289 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyEmergency MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207P00000X
License✔ Licensed in CA · A113953
Definition
An emergency physician focuses on the immediate decision making and action necessary to prevent death or any further disability both in the pre-hospital setting by directing emergency medical technicians and in the emergency department. The emergency physician provides immediate recognition, evaluation, care, stabilization and disposition of a generally diversified population of adult and pediatric patients in response to acute illness and injury.
100 W CALIFORNIA BLVD, Pasadena, CA 91105
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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

Dr. Nicholas Withrow Greco 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 ID6608026893
PECOS Enrollment IDI20121024000601
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

4

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

Hmh Emergency Medical Group, Inc.
0.3 mi
Emergency Medicine
100 W CALIFORNIA BLVD
Pasadena, CA 91105
  • Reassigned Medicare billing, California enrollment
  • 64 clinicians in this Medicare group
NPI 1659383024 (626) 447-0296
Golden State Emergency Physicians Inc
9.2 mi
Emergency Medicine
1401 S GRAND AVE
Los Angeles, CA 90015
  • Reassigned Medicare billing, California enrollment
  • 169 clinicians in this Medicare group
NPI 1770886558 (855) 687-0618
Providence Facey Medical Foundation
25 mi
Urgent Care
14550 SOLEDAD CANYON RD
Santa Clarita, CA 91387
  • Reassigned Medicare billing, California enrollment
  • 684 clinicians in this Medicare group
NPI 1922651561 (818) 837-5559
Exer Medical Corporation
32 mi
Urgent Care
26777 AGOURA RD STE B4
Calabasas, CA 91302
  • Reassigned Medicare billing, California enrollment
  • 256 clinicians in this Medicare group
NPI 1588901532 (818) 880-2225

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 7

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.

Routine electrocardiogram (ecg) using at least 12 leads with interpretation and report only 93010
A routine electrocardiogram (ECG) with 12 leads is a simple, non-invasive test that records the electrical activity of your heart. It helps in identifying heart conditions by detecting irregularities in your heart rhythms. The results are interpreted and a report is provided.
357 services343 patients
Critical care, first 30-74 minutes 99291
Critical care involves immediate and constant attention by a team of specially-trained health professionals. It's for patients with life-threatening conditions, requiring first 30-74 minutes of intense monitoring and treatment.
180 services176 patients
Emergency department visit with high level of medical decision making 99285
An emergency department visit for severe conditions is when you urgently seek medical help due to serious health issues. These could be severe injuries, breathing problems, unbearable pain, or sudden severe illness. Doctors and nurses will provide immediate care to stabilize your condition.
163 services159 patients
Emergency department visit with moderate level of medical decision making 99284
An emergency department visit for a high-severity issue means you're experiencing a serious health problem that needs immediate attention. This could be a severe injury, serious illness, or life-threatening condition. Medical professionals will provide urgent care to stabilize your condition.
38 services38 patients
Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes 99223
Initial hospital inpatient care per day, typically 70 minutes, refers to the daily medical service provided to patients admitted to the hospital. This includes a comprehensive evaluation, diagnosis, treatment plan, and monitoring of your health condition. It ensures your well-being during your hospital stay.
13 services13 patients
New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204
This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.
11 services11 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91105 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
$96.36 typical visit price
range $62.96 – $187.60
Typical copayment $24.09 (range $15.74 – $46.90)
Most-billed visit code 99203
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 20

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

SARAH STEPHENS NP
Nurse Practitioner (Acute Care)
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 397-8300
ROMELIA JALEH BATANG GARCIA RNFA
Registered Nurse (Registered Nurse First Assistant)
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 397-5012
DR. RICHARD A. REED MEDICAL DOCTOR
Radiology (Diagnostic Radiology)
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 397-5139
DR. HENRY LEVENSON M.D.
Pain Medicine (Pain Medicine)
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 256-6010
PASADENA HOSPITAL ASSOCIATION, LTD.
Rehabilitation Unit
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 397-5555
ANIL K HANUMAN D,O.
Hospitalist
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 397-8300
DR. MINDY EVE TITTIGER M.D.
Internal Medicine
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 352-1444
DR. LUIS BALMORE GUTIERREZ M.D.
Radiology (Diagnostic Radiology)
100 W CALIFORNIA BLVD
PASADENA, CA 91105
Los Angeles County (626) 397-5139

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 Nicholas Greco's NPI number?

The NPI number for Nicholas Greco is 1023325289. It was assigned to this individual provider in the NPPES registry on September 9, 2010.

Where is Nicholas Greco located?

Nicholas Greco practices at 100 W California Blvd, Pasadena, CA 91105. The listed phone number is (626) 397-5112.

What is Nicholas Greco's specialty?

The primary specialty registered for this NPI is Emergency Medicine with taxonomy code 207P00000X.

Is Nicholas Greco enrolled in Medicare?

Yes. Nicholas Greco 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 Nicholas Greco's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Nicholas Greco reassigns Medicare benefits to 4 organizations: Hmh Emergency Medical Group, Inc. (Pasadena, CA), Golden State Emergency Physicians Inc (Los Angeles, CA), Providence Facey Medical Foundation (Santa Clarita, CA) and Exer Medical Corporation (Calabasas, 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 Nicholas Greco'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 Nicholas Greco was last updated on August 21, 2013. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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.