Robert D. Marks, MD
Family Medicine Physician · Ennis, MT
Robert D. Marks, MD is a family medicine physician with a practice address in Ennis, Montana, and NPI 1598711673, issued on May 26, 2006. Check the license (Montana 5291, as entered in NPPES) on the Montana Board of Medical Examiners; the Medicare figures below come from public CMS files.
- Name
- Robert D. Marks
- Credential
- MD
- Primary taxonomy
- Family Medicine Physician 207Q00000X
- License number
- 5291 MT
Self-reported in NPPES; status is on the state search - Practice location
- 305 E Main St, Ennis, MT 59729
- Phone
- (406) 682-4223
- Enumerated
- May 26, 2006
- Record last updated
- May 29, 2013 (not updated in 13 years: call before relying on the address or phone)
- Fax
- (406) 682-3874
- Medicaid ID
- 0013858 MT
- Entity
- Type 1 · individual
8 nearest family medicine physician records → All 775 in Montana → Look up another NPI →
Verify Robert D. Marks in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMontana Board of Medical Examiners
Search for license 5291Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
97% fewer Medicare Part D claims than the average family medicine physician in 2024
115 Medicare Part D claims for 45 beneficiaries, against an average of 3,544 among the 117,163 providers of this specialty who prescribed in Part D. Brand-name drugs were 15% of claims.
Most prescribed
- Rosuvastatin Calcium14 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Robert D. Marks among 775 family medicine physician records in Montana
Robert D. Marks, MD is one of 775 family medicine physician records with a practice address in Montana. 75% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 9% of them.
- NPI issued2006 · 9% of these records are older, 50% newer
- In a Medicare fileYes · 75% of these records are
- In the CMS Doctors and Clinicians fileNo · 60% of these records are
- Record last updated2013 · 53% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207Q00000X and a Montana practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
7 family medicine physician records list a practice address in Ennis
They are 7 of the 41 NPPES records with a practice address in Ennis, and 775 family medicine physician records in Montana.
All 775 in Montana → Every provider in Ennis → Family Medicine Physician nationwide →
The 8 family medicine physician records with the nearest ZIP codes
- Brandon Allen, MDEnnis, MT 597291215499421
- Carson Blake, M.D.Ennis, MT 597291932194784
- Dustin Brown, D.O.Ennis, MT 597291821523697
- Bryanna Cordeiro, MDEnnis, MT 597291164051322
- Maura Davenport, M.D.Ennis, MT 597291972896074
- Jaye Swoboda, MDEnnis, MT 597291750314860
- Megan Evans, MDDillon, MT 597251366602559
- Laura Goodell, MDDillon, MT 597251053570929
Common questions
What is Robert D. Marks, MD's NPI number?
Robert D. Marks, MD's National Provider Identifier (NPI) is 1598711673, issued on May 26, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Robert D. Marks, MD located?
The NPPES record lists a practice address at 305 E Main St, Ennis, MT, 59729. Phone: (406) 682-4223. Providers update this record themselves, so call before visiting.
How can I verify Robert D. Marks, MD's license?
NPPES lists Montana license number 5291, as entered by the provider. Search the Montana Board of Medical Examiners at https://ebiz.mt.gov/POL/. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Robert D. Marks, MD prescribe under Medicare Part D?
In 2024, Robert D. Marks, MD had 115 Medicare Part D claims for 45 beneficiaries; the average among family medicine physician prescribers was 3,544. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.