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

MEI LAI SO MD
NPI 1669935441
Internal Medicine in Tucson, AZ

Q: What is Mei So's NPI number?

The NPI number for Mei So is 1669935441. It was assigned to this individual provider in the NPPES registry on April 9, 2019.

Q: What is Mei So's specialty?

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

Q: Is Mei So enrolled in Medicare?

Yes. Mei So 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.

Q: When was this NPI record last updated?

The NPPES record for Mei So was last updated on June 19, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 54 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 April 09, 2019PECOS EnrolledAccepts Medicare Assignment

97.64/100

CMS Quality Rating

6236 E PIMA ST STE 100, TUCSON, AZ 85712(520) 327-6874(520) 327-0028 Get Directions Write a Review

NPPES record last updated: June 19, 2026. Verified against the NPPES registry weekly; last sync: August 09, 2026.

Record update history: Apr 7, 2026, Apr 9, 2019 (2 updates tracked since 2019).

On this page

About Mei Lai So Md NPPES

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

MEI LAI SO MD (NPI 1669935441) is an individual internal medicine provider in Tucson, Arizona, licensed in Arizona (65443) and active in the NPI registry since April 2019. She is enrolled in Medicare PECOS and is a graduate of University Of Arizona College Of Medicine (2019).

NPPES Registry Identity

NPI1669935441

Entity TypeIndividualFemale

Primary Taxonomy207R00000X

Provider Legal NameMEI LAI SOCredential: MD

Location Address6236 E PIMA ST STE 100Tucson, AZ 85712-3164

Mailing Address4801 E Broadway Blvd Ste 251Tucson, AZ 85711-2700 · (520) 327-0460 · Fax (520) 795-0225

Phone(520) 327-6874

Fax(520) 327-0028

Sole ProprietorYes

Medical School CMSUniversity Of Arizona College Of MedicineGraduated 2019

Enumeration DateApril 9, 2019

Last NPPES UpdateJune 19, 20262 updates tracked since enumeration

NPPES CertifiedJune 19, 2026

✔ NPI 1669935441 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal MedicineAllopathic & Osteopathic Physicians

Taxonomy Code207R00000X

License✔ Licensed in AZ · 65443

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.

6236 E PIMA ST STE 100, Tucson, AZ 85712

Open in Google Maps ↗

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Mei Lai So Md 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 ID345575957

PECOS Enrollment IDI20220830003924

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.

Areas of Expertise CMS Part B claims 6

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.

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 99232

Follow-up hospital inpatient care involves daily check-ups while you're admitted in the hospital. Typically, a healthcare provider spends about 25 minutes each day reviewing your condition, adjusting treatment if needed, and answering any questions you might have.

207 services74 patients

Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 99233

Follow-up hospital inpatient care per day typically involves a 35-minute check-up by your healthcare provider. This service includes monitoring your health progress, adjusting your treatment plan if needed, and answering any questions you may have about your condition or care.

96 services42 patients

Hospital discharge day management, more than 30 minutes 99239

Hospital discharge day management over 30 minutes involves a detailed process to ensure a smooth transition from hospital to home. It includes final examinations, discussion of your hospital stay, post-discharge instructions, and coordinating follow-up care.

51 services49 patients

Hospital discharge day management, 30 minutes or less 99238

Hospital discharge day management of 30 minutes or less includes finalizing your treatment, discussing your progress, and planning after-care at home. It ensures you're ready to leave the hospital and continue recovery safely.

19 services19 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.

17 services17 patients

Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 99222

Initial hospital inpatient care is a service where a healthcare provider spends about 50 minutes per day overseeing your care while you're admitted in the hospital. This includes reviewing your health status, planning your treatment, and ensuring your safety and comfort.

11 services11 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 85712 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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

97.64/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored through an Alternative Payment Model

Quality

84.77

Promoting Interoperability

98.67

Improvement Activities

Other Providers at the Same Location NPPES 7

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

ROSANNA R NICOLETTI MD

Family Medicine