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

DR. SIDDHARTHA GANGULY M.D.
NPI 1689767261
Internal Medicine - Hematology in Houston, TX

Q: What is Siddhartha Ganguly's NPI number?

The NPI number for Siddhartha Ganguly is 1689767261. It was assigned to this individual provider in the NPPES registry on October 2, 2006.

Q: What is Siddhartha Ganguly's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology, with taxonomy code 207RH0000X.

Active since October 02, 2006PECOS Enrolled

6445 MAIN STREET, OPC FLOOR 24, HOUSTON, TX 77030(713) 441-9948 Get Directions Write a Review

NPPES record last updated: October 20, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: Jul 7, 2026, Oct 1, 2021 (2 updates tracked since 2021).

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About Dr. Siddhartha Ganguly M.d. NPPES

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

DR. SIDDHARTHA GANGULY M.D. (NPI 1689767261) is an individual hematology provider in Houston, Texas, licensed in Texas (S6620) and active in the NPI registry since October 2006. He is enrolled in Medicare PECOS, is affiliated with Houston Methodist Hospital, and is a graduate of Other (1987).

NPPES Registry Identity

NPI1689767261

Entity TypeIndividualMale

Primary Taxonomy207RH0000X

Provider Legal NameDR. SIDDHARTHA GANGULYCredential: M.D.

Location Address6445 MAIN STREET, OPC FLOOR 24Houston, TX 77030

Mailing Address6445 Main StHouston, TX 77030-1502 · (713) 441-9948

Phone(713) 441-9948

Sole ProprietorNo

Medical School CMSOtherGraduated 1987

Enumeration DateOctober 2, 2006

Last NPPES UpdateOctober 20, 20262 updates tracked since enumeration

NPPES CertifiedOctober 20, 2026

✔ NPI 1689767261 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · HematologyAllopathic & Osteopathic Physicians

Taxonomy Code207RH0000X

License✔ Licensed in TX · S6620

Definition

An internist with additional training who specializes in diseases of the blood, spleen and lymph. This specialist treats conditions such as anemia, clotting disorders, sickle cell disease, hemophilia, leukemia and lymphoma.

6445 MAIN STREET, Houston, TX 77030

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Other Identifiers 4

Medicaid100450610AKS

Other32125027MO · Bcbs Kc

Medicaid208433904MO

Other405970KS · Firstguard

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Oscar Insurance Company, WellPoint.Insurance ›

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. Siddhartha Ganguly 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 ID2961546635

PECOS Enrollment IDI20210602000577

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

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

Tmh Physician Associates PLLC

0.1 mi

Ophthalmology

6550 FANNIN ST, SUITE 447
Houston, TX 77030

Reassigned Medicare billing, Texas enrollment
2,407 clinicians in this Medicare group

NPI 1275779225 (713) 441-7389

Houston Methodist Specialty Physicians

1.1 mi

Otolaryngology

7550 GREENBRIAR DR STE 600
Houston, TX 77030

Reassigned Medicare billing, Texas enrollment
1,579 clinicians in this Medicare group

NPI 1902614332 (281) 414-6055

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 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.

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.

117 services29 patients

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.

98 services42 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.

81 services31 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.

36 services25 patients

Subsequent hospital care with straightforward or low level of medical decision making, per day, if using time, at least 25 minutes 99231

Follow-up hospital inpatient care is a daily service where a healthcare professional checks on your health progress during your hospital stay. Each session typically lasts 15 minutes, involving updates on your condition and adjustments to your treatment plan, if necessary.

21 services18 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.

12 services12 patients

Hospital Affiliations CMS Care Compare 5

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Houston Methodist Hospital

Acute Care Hospitals · Houston, TX

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number450358

Location6565 FanninHouston, TX 77030 · Harris County

Emergency services Birthing friendly

Houston Methodist Baytown Hospital

Acute Care Hospitals · Baytown, TX

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number450424

Location4401 Garth RoadBaytown, TX 77521 · Harris County

Emergency services Birthing friendly

Houston Methodist Clear Lake Hospital

Acute Care Hospitals · Nassau Bay, TX

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number450709

Location18300 Houston Methodist DrNassau Bay, TX 77058 · Harris County

Emergency services Birthing friendly

Houston Methodist Sugarland Hospital

Acute Care Hospitals · Sugar Land, TX

4/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number450820

Location16655 Southwest FreewaySugar Land, TX 77479 · Fort Bend County

Emergency services Birthing friendly

Houston Methodist The Woodlands Hospital

Acute Care Hospitals · The Woodlands, TX

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number670122

Location17201 Interstate 45 SouthThe Woodlands, TX 77385 · Montgomery County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 77030 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

$176.98 typical visit price

range $58.24 – $176.98

Typical copayment $44.24 (range $14.56 – $44.24)

Most-billed visit code 99205

Established Patient

$102.71 typical visit price

range $18.60 – $143.93

Typical copayment $25.67 (range $4.65 – $35.98)

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 13

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

JASLEEN KAUR RANDHAWA M.D

Internal Medicine (Hematology & Oncology)

6445 MAIN STREET, OPC24
HOUSTON, TX 77030

Harris County (713) 441-9948

DR. SUDHA KODALI MBBS

Internal Medicine

6445 MAIN STREET, OPC 22
HOUSTON, TX 77030

Harris County (713) 441-4345

JUN ZHANG MD

Internal Medicine (Hematology & Oncology)

6445 MAIN STREET, OPC 24
HOUSTON, TX 77030

Harris County (713) 441-9948

ARLENE SCORSONE

Nurse Practitioner (Acute Care)

6445 MAIN STREET, OPC - 22ND FLR. SUITE 22.001
HOUSTON, TX 77030

Harris County (713) 441-4345

ROBERT S MCFADDEN M.D.

Internal Medicine (Gastroenterology)

6445 MAIN STREET, OPC 22
HOUSTON, TX 77030

Harris County (713) 441-4345

TAMNEET BASRA MD

Internal Medicine (Transplant Hepatology)

6445 MAIN STREET, OUTPATIENT CENTER, FLOOR 22
HOUSTON, TX 77030

Harris County (713) 441-4345

DR. DAVID W VICTOR III M.D.

Internal Medicine (Transplant Hepatology)

6445 MAIN STREET, OPC 22
HOUSTON, TX 77030

Harris County (137) 441-4345

LONI SAVAGE AGACNP

Nurse Practitioner (Acute Care)

6445 MAIN STREET, OPC 24
HOUSTON, TX 77030

Harris County (713) 441-9948

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 Siddhartha Ganguly's NPI number?

The NPI number for Siddhartha Ganguly is 1689767261. It was assigned to this individual provider in the NPPES registry on October 2, 2006.

Where is Siddhartha Ganguly located?

Siddhartha Ganguly practices at 6445 Main Street Opc Floor 24, Houston, TX 77030. The listed phone number is (713) 441-9948.

What is Siddhartha Ganguly's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology, with taxonomy code 207RH0000X.

Is Siddhartha Ganguly enrolled in Medicare?

Yes. Siddhartha Ganguly 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 Siddhartha Ganguly's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Siddhartha Ganguly reassigns Medicare benefits to 2 organizations: Tmh Physician Associates PLLC (Houston, TX) and Houston Methodist Specialty Physicians (Houston, TX). 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 Siddhartha Ganguly's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Siddhartha Ganguly accept?

Health plans from Oscar Insurance Company and WellPoint list Siddhartha Ganguly as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Siddhartha Ganguly affiliated with any hospitals?

According to CMS data, Siddhartha Ganguly is affiliated with Houston Methodist Hospital, Houston Methodist Baytown Hospital, Houston Methodist Clear Lake Hospital, Houston Methodist Sugarland Hospital and Houston Methodist The Woodlands Hospital.

When was this NPI record last updated?

The NPPES record for Siddhartha Ganguly was last updated on October 20, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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.