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GAY ANN OST MSN, FNP-C
NPI 1912012899
Nurse Practitioner - Family in Denver, CO

Active since August 20, 2006PECOS Enrolled
625 S CLINTON ST APT 14B, DENVER, CO 80247(303) 908-7421(720) 824-1750 Get Directions Write a Review

NPPES record last updated: October 20, 2023. Verified against the NPPES registry weekly; last sync: October 18, 2026.

About Gay Ann Ost Msn, Fnp-c NPPES

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

GAY ANN OST MSN, FNP-C (NPI 1912012899) is an individual family provider in Denver, Colorado, licensed in Colorado (167584) and active in the NPI registry since August 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1912012899
Entity TypeIndividualFemale
Primary Taxonomy363LF0000X
Provider Legal NameGAY ANN OSTCredential: MSN, FNP-C
Location Address625 S CLINTON ST APT 14BDenver, CO 80247-1580
Mailing Address625 S Clinton St Apt 14bDenver, CO 80247-1580 · (303) 908-7421 · Fax (720) 824-1750
Phone(303) 908-7421
Fax(720) 824-1750
Sole ProprietorNo
Enumeration DateAugust 20, 2006
Last NPPES UpdateOctober 20, 2023
NPPES CertifiedApril 28, 2021
✔ NPI 1912012899 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyNurse Practitioner · FamilyPhysician Assistants & Advanced Practice Nursing Providers
Taxonomy Code363LF0000X
License✔ Licensed in CO · 167584
625 S CLINTON ST APT 14B, Denver, CO 80247
Open in Google Maps ↗

Other Identifiers 1

Medicaid05520533CO

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Gay Ann Ost Msn, Fnp-c is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

2

Medicare enrollment records show Gay Ost reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Signify Health Medical Associates, PLLC
647 mi
General Practice
4055 VALLEY VIEW LN STE 700
Dallas, TX 75244
  • Reassigned Medicare billing, Colorado and Oregon enrollments
  • 290 clinicians in this Medicare group
NPI 1750845863 (972) 715-3800
Optum Care Services Company
1,493 mi
Family
10175 LITTLE PATUXENT PKWY FL 6
Columbia, MD 21044
  • Reassigned Medicare billing, Colorado enrollment
  • 3 clinicians in this Medicare group
NPI 1912199415 (410) 379-3522

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

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 80247 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
$89.43 typical visit price
range $58.06 – $174.82
Typical copayment $22.35 (range $14.51 – $43.70)
Most-billed visit code 99203
Established Patient
$102.03 typical visit price
range $18.88 – $142.79
Typical copayment $25.50 (range $4.72 – $35.69)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

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 Gay Ost's NPI number?

The NPI number for Gay Ost is 1912012899. It was assigned to this individual provider in the NPPES registry on August 20, 2006.

Where is Gay Ost located?

Gay Ost practices at 625 S Clinton St Apt 14B, Denver, CO 80247. The listed phone number is (303) 908-7421.

What is Gay Ost's specialty?

The primary specialty registered for this NPI is Nurse Practitioner, specializing in Family, with taxonomy code 363LF0000X.

Is Gay Ost enrolled in Medicare?

Yes. Gay Ost is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Gay Ost's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gay Ost reassigns Medicare benefits to 2 organizations: Signify Health Medical Associates, PLLC (Dallas, TX) and Optum Care Services Company (Columbia, MD). Each 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 Gay Ost's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Gay Ost was last updated on October 20, 2023. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 3 years 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.