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OLIVIA CAROL LETTER
NPI 1598583197
Nurse Anesthetist, Certified Registered in Oshkosh, WI

Active since October 01, 2024Accepts Medicare Assignment
800 ALGOMA BLVD, OSHKOSH, WI 54901(920) 424-1077 Get Directions Write a Review

NPPES record last updated: May 26, 2026. Verified against the NPPES registry weekly; last sync: October 25, 2026.

Record update history: May 26, 2026, Oct 1, 2024 (2 updates tracked since 2024).

About Olivia Carol Letter NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

OLIVIA CAROL LETTER (NPI 1598583197) is an individual nurse anesthetist, certified registered in Oshkosh, Wisconsin, licensed in Wisconsin (161098) and active in the NPI registry since October 2024. She is affiliated with St Vincent Hospital and is a graduate of Other (2026).

NPPES Registry Identity

NPI1598583197
Entity TypeIndividualFemale
Primary Taxonomy367500000X
Provider Legal NameOLIVIA CAROL LETTER
Location Address800 ALGOMA BLVDOshkosh, WI 54901-8610
Mailing Address2396 Crown Pointe BlvdSuamico, WI 54173-8083 · (920) 412-0187
Phone(920) 424-1077
Sole ProprietorNo
Medical School CMSOtherGraduated 2026
Enumeration DateOctober 1, 2024
Last NPPES UpdateMay 26, 20262 updates tracked since enumeration
NPPES CertifiedMay 26, 2026
✔ NPI 1598583197 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse Anesthetist, Certified RegisteredPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code367500000X
License✔ Licensed in WI · 161098
Definition
(1) A licensed registered nurse with advanced specialty education in anesthesia who, in collaboration with appropriate health care professionals, provides preoperative, intraoperative, and postoperative care to patients and assists in management and resuscitation of critical patients in intensive care, coronary care, and emergency situations. Nurse anesthetists are certified following successful completion of credentials and state licensure review and a national examination directed by the Council on Certification of Nurse Anesthetists. (2) A registered nurse who is qualified by special training to administer anesthesia in collaboration with a physician or dentist and who can assist in the care of patients who are in critical condition.
800 ALGOMA BLVD, Oshkosh, WI 54901
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Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Olivia Carol Letter is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID3971074725
PECOS Enrollment IDI20260603000957

Medicare Billing Reassignment

Medicare enrollment records show Olivia Letter reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Green Bay Anesthesia Assoc. Sc
42 mi
Anesthesiology
835 S VAN BUREN ST
Green Bay, WI 54301
  • Reassigned Medicare billing, Wisconsin enrollment
  • 129 clinicians in this Medicare group
NPI 1023065836 (920) 433-0111

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Hospital Affiliations CMS Care Compare 2

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

St Vincent Hospital

Acute Care Hospitals · Green Bay, WI
4/5 CMS rating
OwnershipVoluntary non-profit - Church
CMS Certification Number520075
Location835 S Van Buren StGreen Bay, WI 54301 · Brown County
Emergency services Birthing friendly

St Mary's Hospital Medical Center

Acute Care Hospitals · Green Bay, WI
4/5 CMS rating
OwnershipVoluntary non-profit - Other
CMS Certification Number520097
Location1726 Shawano AveGreen Bay, WI 54303 · Brown County
Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 54901 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$123.69 typical visit price
range $53.90 – $163.24
Typical copayment $30.92 (range $13.47 – $40.81)
Most-billed visit code 99204
Established Patient
$67.37 typical visit price
range $17.40 – $133.76
Typical copayment $16.84 (range $4.35 – $33.44)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

MARIJO EVERS
Nurse Anesthetist, Certified Registered
800 ALGOMA BLVD
OSHKOSH, WI 54901
Winnebago County (920) 424-1234
MICAH GELANI JOHNSON
Student in an Organized Health Care Education/Training Program
800 ALGOMA BLVD
OSHKOSH, WI 54901
Winnebago County (920) 424-1234
NICOLE UELMEN
Student in an Organized Health Care Education/Training Program
800 ALGOMA BLVD
OSHKOSH, WI 54901
Winnebago County (920) 424-1077
MR. WADE CHRISTIAN PEITERSEN LAT
Specialist/Technologist (Athletic Trainer)
800 ALGOMA BLVD, KOLF SPORTS CENTER 169L
OSHKOSH, WI 54901
Winnebago County (920) 424-7138
JOHN J JOHNSEN LAT
Specialist/Technologist (Athletic Trainer)
800 ALGOMA BLVD
OSHKOSH, WI 54901
Winnebago County (920) 424-3225
SAVANNAH FRANCIES
Registered Nurse
800 ALGOMA BLVD
OSHKOSH, WI 54901
Winnebago County (920) 424-1234
SHALYN DANIELLE TREPTOW
Nurse Anesthetist, Certified Registered
800 ALGOMA BLVD
OSHKOSH, WI 54901
Winnebago County (920) 424-1234
KITTIYA HEWITT
Registered Nurse
800 ALGOMA BLVD
OSHKOSH, WI 54901
Winnebago County (920) 424-1234

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Olivia Letter's NPI number?

The NPI number for Olivia Letter is 1598583197. It was assigned to this individual provider in the NPPES registry on October 1, 2024.

Where is Olivia Letter located?

Olivia Letter practices at 800 Algoma Blvd, Oshkosh, WI 54901. The listed phone number is (920) 424-1077.

What is Olivia Letter's specialty?

The primary specialty registered for this NPI is Nurse Anesthetist, Certified Registered with taxonomy code 367500000X.

Is Olivia Letter enrolled in Medicare?

Yes. Olivia Letter is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

Which organization bills Medicare for Olivia Letter's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Olivia Letter reassigns Medicare benefits to Green Bay Anesthesia Assoc. Sc (Green Bay, WI). The reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Olivia Letter's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

Is Olivia Letter affiliated with any hospitals?

According to CMS data, Olivia Letter is affiliated with St Vincent Hospital and St Mary's Hospital Medical Center.

When was this NPI record last updated?

The NPPES record for Olivia Letter was last updated on May 26, 2026. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 5 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.