Quick answers
- Does Zachary W. Marshall accept Medicare assignment?
- Yes. Medicare's clinician data says Zachary W. Marshall 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 Zachary W. Marshall see?
- In 2024, CMS data shows 181 Original Medicare patients and 5,865 services for Zachary W. Marshall. This counts Original Medicare only and measures volume, not quality.
- What is Zachary W. Marshall's NPI number?
- 1912343419. 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 Zachary W. Marshall, 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 | 181 |
|---|---|
| Services billed to Medicare | 5,865 |
| Different services or procedures | 39 |
| Participating Medicare provider | Yes |
| Average age of these patients | 74 |
Most frequent services
- Professional service for preparation and provision of single-dose vial of allergen (95144)1,578 services
- Test for allergy using allergenic extract (95004)1,568 services
- Professional service for preparation and provision of 1 or more antigens (95165)370 services
- Test for allergy using allergenic extract injected into skin (95024)369 services
- Professional service for multiple injections of allergen (95117)209 services
Chronic conditions among these patients
Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).
- High blood pressure75%
- High cholesterol75%
- Arthritis50%
- Asthma37%
- Anxiety34%
- Ischemic heart disease31%
Practice locations
Addresses where Zachary W. Marshall is enrolled with Medicare (CMS data updated October 2, 2026).
- 4710 Bellaire Blvd, Suite 200Bellaire, TX 77401 (713) 661‑1444
Group practices
Medicare enrollment lists Zachary W. Marshall as a member of this group (CMS data updated October 2, 2026).
- McGovern Allergy Clinic, P.A.4 clinicians in the group
Specialties
- Allergy/Immunologyprimary
- Internal Medicinealso
Other allergist and immunologists in Bellaire
Clinicians with the same Medicare primary specialty in Bellaire, TX — not a recommendation.
Other clinicians in McGovern Allergy Clinic, P.A.
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Graduation year | 2013 (13 years since medical school) |
| Gender (as listed) | Male |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| Telehealth | Offers telehealth services |
| NPI (National Provider Identifier) | 1912343419 |
| 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
- 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