Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
NPIDirectory

William Gregory Timmer, DO

Individual provider Emergency Medicine Physician · NPI 1174086128

William Gregory Timmer, DO practises Emergency Medicine in Marietta, Ohio. Qualified in 2019, 7 years ago. Practices with Marietta Memorial Hospital, a 386-clinician group, works from 3 locations and accepts Medicare assignment. Licensed in Ohio.

Years since qualifying
7
Licensed in
OH
In the registry since
2019
What do these letters mean?
DO — Doctor of Osteopathic Medicine
A fully licensed physician, trained like an MD with additional musculoskeletal training. Equivalent practice rights in all 50 states.

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Practice location Address checks out

401 Matthew Street Emergency Dept
Marietta, OH 45750-4575
Phone: (740) 568-5669
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (2)

  • 799 Farson St, Belpre, OH 45714-1082 — (740) 401-1150
  • 1106 Colegate Dr, Marietta, OH 45750-1323 — (740) 568-2000

Specialties & licences

Emergency Medicine Physician (primary) Taxonomy 207P00000X · Licence 34.015660 (OH)

Record details

NPI number1174086128
Entity typeIndividual (Type 1)
GenderMale
Credentials DO
Sole proprietorYes
NPI enumeratedApril 8, 2019
Last updated in NPPESApril 26, 2022
Certification dateApril 26, 2022

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyEMERGENCY MEDICINE
Medical schoolOTHER
Graduated 2019 (7 years in practice)
Group practice Marietta Memorial Hospital — 386 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients454
Services billed 569 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at Marietta Memorial Hospital

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 386 clinicians in the practice; 12 are shown here.

Other providers in Marietta