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

Mrs. Marissa Anne Ontis, FNP-C

Individual provider Family Nurse Practitioner · NPI 1629704929

Mrs. Marissa Anne Ontis, FNP-C is a Nurse Practitioner in Alton, Illinois. Qualified in 2022, 4 years ago. Practices with Healogics Specialty Physicians of Illinois, LLC, a 15-clinician group and accepts Medicare assignment. Licensed in Illinois.

Years since qualifying
4
Licensed in
IL
In the registry since
2022
What do these letters mean?
FNP-C — Family Nurse Practitioner, Certified
A family nurse practitioner certified by the AANP.

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Practice location Address checks out

1 Memorial Dr # G181
Alton, IL 62002-6755
Phone: (618) 433-7066
Fax: (618) 433-7060
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Family Nurse Practitioner (primary) Taxonomy 363LF0000X · Licence 209025582 (IL)

Record details

NPI number1629704929
Entity typeIndividual (Type 1)
GenderFemale
Credentials FNP-C
Sole proprietorNo
NPI enumeratedJuly 28, 2022
Last updated in NPPESMay 1, 2026
Certification dateMay 1, 2026

Medicare enrollment

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

Medicare specialtyNURSE PRACTITIONER
Medical schoolOTHER
Graduated 2022 (4 years in practice)
Group practice Healogics Specialty Physicians Of Illinois, Llc — 15 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount

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