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

Mrs. Mary B Ernst, FNP

Individual provider Acute Care Nurse Practitioner · NPI 1487694659

Mrs. Mary B Ernst, FNP is a Nurse Practitioner in Saint Peters, Missouri. Qualified in 1998, 28 years ago. Practices with Physician Groups Lc, a 524-clinician group, works from 2 locations and accepts Medicare assignment. Licensed in Missouri.

Years since qualifying
28
Licensed in
MO
In the registry since
2006
Specialties on file
3
What do these letters mean?
FNP — Family Nurse Practitioner
A nurse practitioner who treats patients of all ages, much like a family doctor.

See every abbreviation used in this directory →

Practice location Address checks out

107 Piper Hill Dr
Saint Peters, MO 63376-1620
Phone: (636) 477-8757
Fax: (314) 219-6241
Show map & directions

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

Additional practice locations (1)

  • 1520 Wentzville Pkwy, Wentzville, MO 63385-3408 — (636) 497-4060

Specialties & licences

Nurse Practitioner (primary) Taxonomy 363L00000X · Licence 2014010124 (MO)
Acute Care Nurse Practitioner Taxonomy 363LA2100X · Licence 2014010124 (MO)
Acute Care Nurse Practitioner Taxonomy 363LA2100X · Licence 073032 (MO)

Record details

NPI number1487694659
Entity typeIndividual (Type 1)
GenderFemale
Credentials FNP
Sole proprietorNo
NPI enumeratedJune 7, 2006
Last updated in NPPESMay 3, 2022
Certification dateMay 3, 2022

Medicare enrollment

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

Medicare specialtyNURSE PRACTITIONER
Medical schoolOTHER
Graduated 1998 (28 years in practice)
Group practice Physician Groups Lc — 524 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
Practice locations3 on file with Medicare

Other providers in Saint Peters