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

DR. HOLLIS J. C. UNDERWOOD M.D.
NPI 1770640369
Internal Medicine in Scottsdale, AZ

Q: What is Hollis Underwood's NPI number?

The NPI number for Hollis Underwood is 1770640369. It was assigned to this individual provider in the NPPES registry on January 2, 2007.

Q: What is Hollis Underwood's specialty?

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

Q: Is Hollis Underwood enrolled in Medicare?

No. Hollis Underwood has opted out of Medicare through October 1, 2028. Care is provided under private contracts, and Medicare does not pay for services furnished by providers who have opted out. The provider remains eligible to order and refer services for Medicare patients.

Q: When was this NPI record last updated?

The NPPES record for Hollis Underwood was last updated on October 22, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 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.

Active since January 02, 2007Opted out of Medicare · through Oct 1, 2028

20159 N SCOTTSDALE RD STE 150, SCOTTSDALE, AZ 85255(480) 378-7000(480) 378-9200 Get Directions Write a Review

NPPES record last updated: October 22, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Sep 10, 2024, Apr 8, 2020 (2 updates tracked since 2020).

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About Dr. Hollis J. C. Underwood M.d. NPPES

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

DR. HOLLIS J. C. UNDERWOOD M.D. (NPI 1770640369) is an individual internal medicine provider in Scottsdale, Arizona, licensed in Arizona (22415) and active in the NPI registry since January 2007. She has opted out of Medicare through October 1, 2028 and remains eligible to order and refer and is a graduate of Howard University College Of Medicine (1983).

NPPES Registry Identity

NPI1770640369

Entity TypeIndividualFemale

Primary Taxonomy207R00000X

Provider Legal NameDR. HOLLIS J. C. UNDERWOODCredential: M.D.

Location Address20159 N SCOTTSDALE RD STE 150Scottsdale, AZ 85255-0060

Mailing Address102 Woodmont Blvd Ste 600Nashville, TN 37205-5250 · (888) 987-1151

Phone(480) 378-7000

Fax(480) 378-9200

Sole ProprietorNo

Medical School CMSHoward University College Of MedicineGraduated 1983

Enumeration DateJanuary 2, 2007

Last NPPES UpdateOctober 22, 20262 updates tracked since enumeration

NPPES CertifiedOctober 22, 2026

✔ NPI 1770640369 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in AZ · 22415

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.

Also ListedSpecialistTaxonomy 174400000X · License 22415 (AZ)

20159 N SCOTTSDALE RD STE 150, Scottsdale, AZ 85255

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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

ⓘ

Opted out of Medicare

Dr. Hollis J. C. Underwood M.d. has filed a Medicare opt-out affidavit. Services are provided under private contract between the provider and the patient, and are not billed to or reimbursed by Medicare. The opt-out is on file from October 1, 2026 through October 1, 2028.

Opt-Out Effective DateOctober 1, 2026

Opt-Out In Effect ThroughOctober 1, 2028Opt-out affidavits renew automatically every two years unless cancelled

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesAn opted-out provider can still order and refer for Medicare patients in the categories marked above, even though their own services are not covered.

Areas of Expertise CMS Part B claims 2

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 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.

434 services239 patients

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.

85 services74 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 85255 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

$127.71 typical visit price

range $55.44 – $168.60

Typical copayment $31.92 (range $13.86 – $42.15)

Most-billed visit code 99204

Established Patient

$98.00 typical visit price

range $17.72 – $137.41

Typical copayment $24.50 (range $4.43 – $34.35)

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.

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Blood glucose test or reagent strips for home blood glucose monitor, per 50 strips A4253

DME-Other DME · category DE017N

11 suppliers14 claims28 services$5.17 avg. paid by Medicare

Supply allowance for therapeutic continuous glucose monitor (cgm), includes all supplies and accessories, 1 month supply = 1 unit of service K0553

DME-Other DME · category DE017N

3 suppliers19 claims19 services$200.78 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 6

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

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