What is Mark Liong's NPI number?

Mark Liong's National Provider Identifier (NPI) is 1346422078, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.

What is Mark Liong's specialty?

Mark Liong is listed in the NPPES registry with a primary specialty of Nephrology Physician (Allopathic & Osteopathic Physicians).

Where is Mark Liong located?

Mark Liong's practice location on file with NPPES is 1901 S 1st St Ste 600, Mcallen, TX 78503-1228.

What is Mark Liong's phone number?

The practice phone number listed in the NPPES registry for Mark Liong is (956) 631-6136.

Does Mark Liong accept Medicare?

Mark Liong is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.

Is Mark Liong's NPI active?

Yes — Mark Liong's NPI (1346422078) is active in the NPPES registry as of the last update on 2015-01-08.

IndividualActiveAccepts Medicare

Mark Liong, M.D.

NPI 1346422078 · Nephrology Physician · Mcallen, TX

Mark Liong, M.D. is a Nephrology Physician provider in Mcallen, TX (NPI 1346422078).

Provider details

NPI number: 1346422078
Entity type: Individual
Primary specialty: Nephrology PhysicianAllopathic & Osteopathic Physicians
Credential: M.D.
Sex: Male
Sole proprietor: No
License: P4673 (TX)

Practice location

1901 S 1st St Ste 600

Mcallen, TX 78503-1228

Phone: (956) 631-6136

Fax: (956) 631-1848

Street-level locationGet directions

More TX providers

Mailing address

1901 S 1st St Ste 600

Mcallen, TX 78503-1228

Specialties & taxonomies

Nephrology PhysicianPrimary207RN0300XLicense P4673 (TX)
Allopathic & Osteopathic Physicians

Enrolled with Medicare as Practitioner - Nephrology · source: CMS PECOS Public Provider Enrollment (2026.04.01)

Profile Score

Detailed profile(75/100 index)

A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.

Registry tenure25% of score
18 yrs in NPPES registry
Profile completeness25% of score
100% of core fields populated
Practice footprint15% of score
1 documented practice location
Medicare service volume (vs. specialty peers)25% of score
934 Medicare services, 2024 (ranked within specialty)
Open Payments transparency10% of score
Has Open Payments disclosures (2024)

Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our methodology.

What this provider does (Medicare)

Based on Medicare fee-for-service claims, 2024; not all care is captured.

Service (HCPCS)	Medicare services	Typical Medicare-allowed (2024)
Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232	230	$79
Dialysis Services, 4 Or More Physician Visits Per Month (20 Years Or Older)90960	229	$357
Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233	220	$118
Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214	93	$129
Dialysis Services, 2-3 Physician Visits Per Month (20 Years Or Older)90961	79	$297
Hemodialysis Procedure With Physician Evaluation90935	53

What this provider prescribes (Medicare Part D)

Top drugs by Medicare Part D claim volume, 2024 · 20 distinct drugs on file.

Drug	Part D claims (2024)	Beneficiaries
Sevelamer Carbonate	312	64
Ferric Citratebrand: Auryxia	278	50
Nifedipinebrand: Nifedipine Er	83	25
Sodium Zirconium Cyclosilicatebrand: Lokelma	82	22
Sucroferric Oxyhydroxidebrand: Velphoro	77	16
Amlodipine Besylate	54	14
Patiromer Calcium Sorbitexbrand: Veltassa

Transparency — industry payments

Based on CMS Open Payments, 2024; not all care is captured.

$649 across 23 records (Open Payments 2024)

Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.

Enumerated: 2007-12-05
Last updated: 2015-01-08

Frequently asked questions

What is Mark Liong's NPI number?: Mark Liong's National Provider Identifier (NPI) is 1346422078, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
What is Mark Liong's specialty?: Mark Liong is listed in the NPPES registry with a primary specialty of Nephrology Physician (Allopathic & Osteopathic Physicians).
Where is Mark Liong located?: Mark Liong's practice location on file with NPPES is 1901 S 1st St Ste 600, Mcallen, TX 78503-1228.
What is Mark Liong's phone number?: The practice phone number listed in the NPPES registry for Mark Liong is (956) 631-6136.
Does Mark Liong accept Medicare?: Mark Liong is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
Is Mark Liong's NPI active?: Yes — Mark Liong's NPI (1346422078) is active in the NPPES registry as of the last update on 2015-01-08.

Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.

What this provider does (Medicare)

Based on Medicare fee-for-service claims, 2024; not all care is captured.

Service (HCPCS)	Medicare services	Typical Medicare-allowed (2024)
Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 35 Minutes99232	230	$79
Dialysis Services, 4 Or More Physician Visits Per Month (20 Years Or Older)90960	229	$357
Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233	220	$118
Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214	93	$129
Dialysis Services, 2-3 Physician Visits Per Month (20 Years Or Older)90961	79	$297
Hemodialysis Procedure With Physician Evaluation90935	53

What this provider prescribes (Medicare Part D)

Top drugs by Medicare Part D claim volume, 2024 · 20 distinct drugs on file.

Drug	Part D claims (2024)	Beneficiaries
Sevelamer Carbonate	312	64
Ferric Citratebrand: Auryxia	278	50
Nifedipinebrand: Nifedipine Er	83	25
Sodium Zirconium Cyclosilicatebrand: Lokelma	82	22
Sucroferric Oxyhydroxidebrand: Velphoro	77	16
Amlodipine Besylate	54	14
Patiromer Calcium Sorbitexbrand: Veltassa

Transparency — industry payments

Based on CMS Open Payments, 2024; not all care is captured.

$649 across 23 records (Open Payments 2024)

Provider details

Practice location

Mailing address

Specialties & taxonomies

Profile Score

What this provider does (Medicare)

What this provider prescribes (Medicare Part D)

Transparency — industry payments

Registry dates

Frequently asked questions

Specialties & taxonomies

Frequently asked questions

Profile Score

What this provider does (Medicare)

What this provider prescribes (Medicare Part D)

Transparency — industry payments