Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.
NPIDirectory

Dr. Nicholas John-James Lettner-Knowlton, MD

Individual provider Internal Medicine Physician · NPI 1356075147

Dr. Nicholas John-James Lettner-Knowlton, MD is an Internal Medicine in Saginaw, Michigan. Qualified in 2022, 4 years ago. Practices with Saginaw Cooperative Hospitals Inc, a 75-clinician group and accepts Medicare assignment. Licensed in Michigan.

Years since qualifying
4
Licensed in
MI
In the registry since
2022
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Claim this listing Report a problem Suggest an edit

Practice location Address checks out

1015 S Washington Ave
Saginaw, MI 48601-2556
Phone: (989) 746-7500
Fax: (989) 746-7728
Show map & directions

Directions in Google Maps · Apple Maps · OpenStreetMap

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Internal Medicine Physician (primary) Taxonomy 207R00000X · Licence 4301514040 (MI)
Hospitalist Physician Taxonomy 208M00000X · Licence 4301514040 (MI)

Record details

NPI number1356075147
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJuly 15, 2022
Last updated in NPPESJanuary 9, 2026
Certification dateJanuary 9, 2026

Medicare enrollment

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

Medicare specialtyINTERNAL MEDICINE
Medical schoolOTHER
Graduated 2022 (4 years in practice)
Group practice Saginaw Cooperative Hospitals Inc — 75 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

Other providers in Saginaw