Individual provider

Dennis Ruff, M.D.

Internal Medicine Physician

Dennis Ruff, M.D. is an Internal Medicine Physician in San Antonio, TX, registered under NPI 1003035718. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.

Getting there

Here is what surrounds this office in San Antonio, based on OpenStreetMap data collected Aug 31, 2026. Parking is available about 0.35 mi away. If you arrive early, there is a coffee shop 0.24 mi away.

8307 GAULT LN, San Antonio, TX 78209 Open in Google Maps →

Getting here and what is nearby

Parking 0.20 mi ~5 min
Parking 0.21 mi ~5 min
Coffee Dutch Bros. Coffee 0.24 mi ~5 min

8222 Broadway Road, San Antonio 78209

Mo-Th 05:00-22:00; Fr-Sa 05:00-23:00; Su 05:00-22:00

Website

Directions in Google Maps →

Restaurant Raising Cane's 0.32 mi ~7 min

Broadway, San Antonio

Directions in Google Maps →

Restaurant Jim's 0.34 mi ~7 min

8427 Broadway, San Antonio 78209

Directions in Google Maps →

Parking 0.35 mi ~7 min
Restaurant Whataburger 0.38 mi ~8 min

8426 Broadway, San Antonio 78209

24/7

+1 210-828-5720

Website

Directions in Google Maps →

Hotel Days Inn by Wyndham San Antonio Airport 0.39 mi ~8 min

542 Northeast Loop 410, San Antonio 78216

+1 210-899-4707

Website

Directions in Google Maps →

Convenience Timewise Food Store 0.44 mi ~9 min

8501 Broadway, San Antonio 78217

Directions in Google Maps →

Hotel SpringHill Suites San Antonio Airport 0.44 mi ~9 min

514 Northeast Loop 410, San Antonio 78216

+1 210-804-2266

Website

Directions in Google Maps →

Gas station Shell 0.45 mi ~10 min
Hotel Comfort Inn & Suites Airport 0.46 mi ~10 min

8640 Crownhill Boulevard, San Antonio 78209

+1 210-571-7626

Website

Directions in Google Maps →

OpenStreetMap via Overpass · ODbL 800 m radius Updated Aug 31, 2026

Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.

Credentials and Medicare

State licence
LicenceStateSpecialty
G9525 TX Internal Medicine Physician primary

This provider holds licence G9525 issued in TX. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.

Medicare (PECOS)

This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.

What Internal Medicine covers

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. NUCC Health Care Provider Taxonomy, code 207R00000X
Allopathic & Osteopathic Physicians Internal Medicine

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1003035718 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateApr 24, 2007
Last updatedJul 8, 2007
StatusActive
Sole proprietorYes
GenderMale
CredentialM.D.
Practice address 8307 GAULT LN
San Antonio, TX 78209
(210) 798-5112
This record was last updated on Jul 8, 2007, roughly 19 years ago. Address and phone details that old are frequently out of date. Verify by phone before travelling to the address shown.

Number check

1003035718 passes the NPI check digit test The final digit 8 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 0 0 3 0 3 5 7 1
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 0 0 3 0 3 1 7 2

Sum = 42 · next multiple of 10 = 50 · check digit = 8 · actual last digit = 8

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1003035718?
NPI 1003035718 is the National Provider Identifier assigned to Dennis Ruff, M.D. in San Antonio, TX. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Internal Medicine Physician cover?
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…
How do I contact Dennis Ruff, M.D.?
The phone number on file with NPPES is (210) 798-5112, last updated Jul 8, 2007. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Where do I park when visiting Dennis Ruff, M.D.?
Parking is about 0.35 mi from the office. Distances are straight-line estimates from OpenStreetMap, so walking routes may be slightly longer.
Is NPI 1003035718 a valid number?
Yes. 1003035718 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.