Katherine Madison Macmillan, M.D.
Gastroenterology (CMS) · Simpsonville, SC
At a glance
741 Se Main St, Simpsonville, SC 29681-3237
Published activity: Colonoscopy · Upper gastrointestinal (GI) endoscopy for acid reflux. View counts and coverage
NPPES record updated Feb 23, 2026. Public records can lag behind changes at a practice.
Before you call: a quick checklist
- Are you accepting new patients?
- Do you accept my specific insurance plan?
- Do you provide the service I need at this address?
- Do I need a referral, and what is the earliest appointment?
Insurance participation and appointment availability are not established by these public records.
Medicare & insurance
Insurance participation is not established by these public records. Ask the practice and your insurer about your specific plan and this location.
How to check your coverage
Use your plan’s provider directory or the member-services number on your insurance card. Confirm the clinician, practice address, service, and whether a referral is required. A missing opt-out record does not establish Medicare acceptance.
Check the official Medicare directory ↗Practice location
741 Se Main StSimpsonville, SC 29681-3237
Additional reported practice locations
727 Se Main St Ste 340Simpsonville, SC 296813249
Phone: 8644552888
Fax: 8644552885 13400 E Shea Blvd
Scottsdale, AZ 852595499
Phone: 4803018000
Education & affiliations
- Medical / professional school
- Not reported in this file
- Graduation year
- 2017
- CMS specialties
- Gastroenterology
Practice groups
Reported hospital affiliations
- Prisma Health Patewood Hospital Greenville, SC
- Prisma Health Baptist Easley Hospital Easley, SC
- Prisma Health Greenville Memorial Hospital Greenville, SC
- Prisma Health Hillcrest Hospital Simpsonville, SC
- Prisma Health Laurens County Hospital Clinton, SC
Graduation year does not establish years in practice. A reported affiliation does not establish employment, current admitting privileges, or insurance participation.
Source: CMS National Downloadable File · Published Oct 15, 2026.
Source: CMS Facility Affiliation Data · Published Oct 15, 2026.
Procedures in the public data
Reported activity can help you ask more informed questions about a practice’s services.
| Procedure category | Published Medicare activity |
|---|---|
| Colonoscopy | 45 |
| Upper gastrointestinal (GI) endoscopy for acid reflux | 128 |
CMS uses a one-year claims window with a reporting lag. Counts cover the Medicare activity included by CMS, not all patients. “1–10” is a published range. Volume is not a quality or outcomes score. Coverage and methodology
Source: CMS Utilization Data · Published Oct 15, 2026.
Service-mix comparison is unavailable for this NPI in the imported Medicare service file.
Industry-reported general payments
Includes reported transfers of value, such as meals, travel, or consulting. Payments do not establish improper conduct or quality of care. Research funding and ownership values are excluded from this total.
See payment purposes and reporting companies
Reported purposes
| Purpose | Amount |
|---|---|
| Travel and lodging | $3,235.37 |
| Food and beverage | $1,327.56 |
Reporting companies
| Company | Amount |
|---|---|
| BOSTON SCIENTIFIC CORPORATION | $3,371.04 |
| OVESCO ENDOSCOPY USA, INC. | $429.22 |
| JANSSEN BIOTECH, INC. | $208.78 |
| ERBE USA INC | $157.98 |
| GENZYME CORPORATION | $77.91 |
| ARDELYX, INC. | $66.21 |
| ABBVIE INC. | $55.93 |
| IPSEN BIOPHARMACEUTICALS, INC | $49.26 |
| Other reporting companies | $146.60 |
Source: CMS 2025 payments grouped by covered recipient and nature of payments · Published Jun 30, 2026.
Professional details: NPI, taxonomy & registry record
Registry details
- Primary taxonomy
- Gastroenterology (CMS)
- Taxonomy code
- 207RG0100X
- Enumeration date
- Apr 10, 2017
- Record updated
- Feb 23, 2026
More registry details
- Provider type
- Individual · Type 1
- Reported credentials
- M.D.
Reported taxonomies and licenses
207R00000X
License reported: 85580 SC
207R00000X
License reported: 009641 GA
207RG0100X
License reported: 72379 AZ
207RG0100X · Primary
License reported: 85580 SC
License numbers and credentials are reported to NPPES; HCPList does not independently verify them.
Practice location
741 Se Main StSimpsonville, SC 29681-3237
- Phone
- (864) 522-8420
- Fax
- (864) 522-8425
Mailing address
300 E MCBEE AVE STE 300GREENVILLE, SC 296012899
Information may be outdated or incomplete. Confirm details directly with the practice. HCPList is an independent directory and is not affiliated with CMS.
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