Quick answers
- Does John D. Butler Jr. accept Medicare assignment?
- Yes. Medicare's clinician data says John D. Butler Jr. accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does John D. Butler Jr. see?
- In 2024, CMS data shows 12 Original Medicare patients and 18 services for John D. Butler Jr.. This counts Original Medicare only and measures volume, not quality.
- What is John D. Butler Jr.'s NPI number?
- 1447303458. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for John D. Butler Jr., data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.
| Original Medicare patients | 12 |
|---|---|
| Services billed to Medicare | 18 |
| Different services or procedures | 14 |
| Participating Medicare provider | Yes |
| Average age of these patients | 71 |
Hospitals where John D. Butler Jr. works
Medicare's Facility Affiliation Data lists John D. Butler Jr. at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.
- Holy Cross HospitalSilver Spring, MD · Acute Care Hospital · Medicare rating: 2 of 5 stars · Emergency services: not listed by Medicare · CCN 210004
Practice locations
Addresses where John D. Butler Jr. is enrolled with Medicare (CMS data updated October 2, 2026).
- 10810 Connecticut AveKensington, MD 20895 (301) 929‑7100
- 1221 Mercantile LnLargo, MD 20774 (301) 618‑5700
- 655 Watkins Mill RdGaithersburg, MD 20879 (240) 632‑4000
Group practices
Medicare enrollment lists John D. Butler Jr. as a member of this group (CMS data updated October 2, 2026).
- Kaiser Foundation Health Plan of the Mid Atlantic States, Inc1,899 clinicians in the group
Specialties
- General Surgeryprimary
Other general surgeons in Kensington
Clinicians with the same Medicare primary specialty in Kensington, MD — not a recommendation.
Other clinicians in Kaiser Foundation Health Plan of the Mid Atlantic States, Inc
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Johns Hopkins University School Of Medicine |
| Graduation year | 1986 (40 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1447303458 |
| Corrections | Report an error or suggest an update → |
Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.
Sources
- Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
- Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians