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DR. HEATHER CAROLYN WILLIAMSON DO
NPI 1700880358
Family Medicine in O Fallon, MO

Active since June 10, 2005PECOS Enrolled
3449 PHEASANT MEADOW DR, STE 107, O FALLON, MO 63368(636) 379-4140(636) 379-4132 Get Directions Write a Review

NPPES record last updated: March 13, 2013. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Heather Carolyn Williamson Do NPPES

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

DR. HEATHER CAROLYN WILLIAMSON DO (NPI 1700880358) is an individual family medicine provider in O Fallon, Missouri, licensed in Missouri (2001026591) and active in the NPI registry since June 2005. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1700880358
Entity TypeIndividualFemale
Primary Taxonomy207Q00000X
Provider Legal NameDR. HEATHER CAROLYN WILLIAMSONCredential: DO
Location Address3449 PHEASANT MEADOW DR, STE 107O Fallon, MO 63368-7364
Mailing Address670 Mason Ridge Center Dr, Ste 300Saint Louis, MO 63141-8573 · (636) 379-4140 · Fax (636) 379-4132
Phone(636) 379-4140
Fax(636) 379-4132
Sole ProprietorNo
Enumeration DateJune 10, 2005
Last NPPES UpdateMarch 13, 2013
✔ NPI 1700880358 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyFamily MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207Q00000X
License✔ Licensed in MO · 2001026591
Definition
Family Medicine is the medical specialty which is concerned with the total health care of the individual and the family. It is the specialty in breadth which integrates the biological, clinical, and behavioral sciences. The scope of family medicine is not limited by age, sex, organ system, or disease entity.
3449 PHEASANT MEADOW DR, O Fallon, MO 63368
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Other Identifiers 5

Medicare UPINH97226
Medicare ID-Type Unspecified908714095
Medicaid204028005MO
Medicare PIN908714748MO
Medicare PIN908714740MO

Medicare Participation & PECOS CMS

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

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Heather Carolyn Williamson Do 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 Heather Williamson reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Mercy Hospitals East Communities
15 mi
Audiologist
621 S NEW BALLAS RD STE 385A
Saint Louis, MO 63141
  • Reassigned Medicare billing, Missouri enrollment
  • 241 clinicians in this Medicare group
NPI 1255790762 (314) 251-5850
Freeman-Oak Hill Health System
238 mi
General Acute Care Hospital
1102 W 32ND ST
Joplin, MO 64804
  • Reassigned Medicare billing, Missouri enrollment
  • 171 clinicians in this Medicare group
NPI 1891809679 (417) 347-1111

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 63368 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
$86.32 typical visit price
range $55.65 – $169.38
Typical copayment $21.58 (range $13.91 – $42.34)
Most-billed visit code 99203
Established Patient
$98.37 typical visit price
range $17.76 – $137.92
Typical copayment $24.59 (range $4.44 – $34.48)
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.

Other Providers at the Same Location NPPES

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

PHYSICIAN GROUPS LC
Clinic/Center (Multi-Specialty)
3449 PHEASANT MEADOW DR, SUITE 107
O FALLON, MO 63368
St. Charles County (636) 379-4140

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 Heather Williamson's NPI number?

The NPI number for Heather Williamson is 1700880358. It was assigned to this individual provider in the NPPES registry on June 10, 2005.

Where is Heather Williamson located?

Heather Williamson practices at 3449 Pheasant Meadow Dr Ste 107, O Fallon, MO 63368. The listed phone number is (636) 379-4140.

What is Heather Williamson's specialty?

The primary specialty registered for this NPI is Family Medicine with taxonomy code 207Q00000X.

Is Heather Williamson enrolled in Medicare?

Yes. Heather Williamson is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Heather Williamson's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Heather Williamson reassigns Medicare benefits to 2 organizations: Mercy Hospitals East Communities (Saint Louis, MO) and Freeman-Oak Hill Health System (Joplin, MO). 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 Heather Williamson'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 Heather Williamson was last updated on March 13, 2013. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 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.