DR. GREGORY MARK GERRISH M.D.
NPI 1992097703
Surgery in Watertown, SD

Q: What is Gregory Gerrish's NPI number?

The NPI number for Gregory Gerrish is 1992097703. It was assigned to this individual provider in the NPPES registry on May 12, 2011.

Q: What is Gregory Gerrish's specialty?

The primary specialty registered for this NPI is Surgery with taxonomy code 208600000X.

Q: When was this NPI record last updated?

The NPPES record for Gregory Gerrish was last updated on August 17, 2016. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.

Active since May 12, 2011PECOS EnrolledAccepts Medicare Assignment

97.75/100

CMS Quality Rating

401 9TH AVE. NW, PRAIRIE LAKES HOSPITAL, WATERTOWN, SD 57201(605) 882-7000 Get Directions Write a Review

NPPES record last updated: August 17, 2016. Verified against the NPPES registry weekly; last sync: November 01, 2026.

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About Dr. Gregory Mark Gerrish M.d. NPPES

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

DR. GREGORY MARK GERRISH M.D. (NPI 1992097703) is an individual surgery provider in Watertown, South Dakota, licensed in South Dakota (10080) and active in the NPI registry since May 2011. He is enrolled in Medicare PECOS, is affiliated with Ortonville Area Health Services, and is a graduate of Sanford School Of Medicine Of University Of South Dakota (2011).

NPPES Registry Identity

NPI1992097703

Entity TypeIndividualMale

Primary Taxonomy208600000X

Provider Legal NameDR. GREGORY MARK GERRISHCredential: M.D.

Location Address401 9TH AVE. NW, PRAIRIE LAKES HOSPITALWatertown, SD 57201-1623

Mailing AddressPo Box 1210Watertown, SD 57201-6210 · (605) 670-8594

Phone(605) 882-7000

Sole ProprietorNo

Medical School CMSSanford School Of Medicine Of University Of South DakotaGraduated 2011

Enumeration DateMay 12, 2011

Last NPPES UpdateAugust 17, 2016

✔ NPI 1992097703 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtySurgeryAllopathic & Osteopathic Physicians

Taxonomy Code208600000X

License✔ Licensed in SD · 10080

Definition

A general surgeon has expertise related to the diagnosis - preoperative, operative and postoperative management - and management of complications of surgical conditions in the following areas: alimentary tract; abdomen; breast, skin and soft tissue; endocrine system; head and neck surgery; pediatric surgery; surgical critical care; surgical oncology; trauma and burns; and vascular surgery. General surgeons increasingly provide care through the use of minimally invasive and endoscopic techniques. Many general surgeons also possess expertise in transplantation surgery, plastic surgery and cardiothoracic surgery.

Also ListedStudent in an Organized Health Care Education/Training ProgramTaxonomy 390200000X

401 9TH AVE. NW, Watertown, SD 57201

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Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Avera Health Plans, Sanford Health Plan, Wellmark of South Dakota, Inc..Insurance ›

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

Dr. Gregory Mark Gerrish M.d. 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 ID8527363712

PECOS Enrollment IDI20160915001127, I20161130001918

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 Reassignment

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

Prairie Lakes Health Care System Inc

Same address

Rural

401 9TH AVE NW
Watertown, SD 57201

Reassigned Medicare billing, Minnesota and South Dakota enrollments
10 clinicians in this Medicare group

NPI 1720166002 (605) 882-7000

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

Areas of Expertise CMS Part B claims 15

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213

This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.

67 services58 patients

Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43239

This procedure involves using a thin, flexible tube with a light and camera, known as an endoscope, to examine the esophagus, stomach, and upper part of the small intestine. Small tissue samples are taken for further examination to help diagnose various conditions.

62 services60 patients

Removal of polyps or growths of large bowel using an endoscope with mechanical snare 45385

This procedure involves using a thin, flexible tube called an endoscope to examine the large bowel. If any abnormal growths or polyps are found, a tool called a mechanical snare is used to remove them. This is a common method to prevent potential health issues.

55 services54 patients

New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203

This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.

45 services45 patients

Diagnostic exam of esophagus, stomach, and/or upper small bowel using a flexible endoscope 43235

This procedure, known as an upper endoscopy, involves inserting a thin, flexible tube with a camera down the throat to examine the esophagus, stomach, and upper small bowel. It helps diagnose conditions like ulcers or inflammation.

29 services29 patients

Diagnostic exam of large bowel using a flexible endoscope 45378

This procedure, known as a colonoscopy, involves using a flexible tube with a light and camera to examine the large intestine. It helps detect any abnormalities such as polyps or inflammation. It's a standard procedure to ensure gut health.

23 services23 patients

Colorectal cancer screening; colonoscopy on individual at high risk G0105

Colorectal cancer screening, specifically a colonoscopy, is a preventive measure for those at high risk. A thin, flexible tube with a camera inspects the colon to spot any abnormal growths. This test helps detect potential issues early, enhancing the effectiveness of treatment.

22 services22 patients

Initial hospital care with straightforward or low level of medical decision making, per day, if using time, at least 40 minutes 99221

Initial hospital inpatient care refers to the first day of your stay in the hospital. This service typically includes a 30-minute check-up with a healthcare professional. They'll assess your health, discuss your condition, and plan your treatment. It's part of ensuring you receive the best possible care.

20 services20 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.

19 services17 patients

Biopsy of large bowel using a flexible endoscope 45380

A biopsy of the large bowel using a flexible endoscope is a procedure where a thin, flexible tube with a camera is inserted through the rectum to examine the bowel. If abnormal tissue is found, a small sample is taken for further examination. This helps in diagnosing conditions like inflammation, polyps, or cancer.

18 services18 patients

Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk G0121

Colorectal cancer screening, such as a colonoscopy, is a preventive measure to detect early signs of cancer in the large intestine. For individuals not at high risk, it's typically recommended at age 50. A small, flexible tube with a camera is used to examine your colon. It's a safe, effective way to catch issues early.

18 services18 patients

Balloon dilation of esophagus, stomach, and/or upper small bowel using a flexible endoscope, less than 3.0 cm 43249

This procedure involves using a flexible tube with a camera, called an endoscope, to gently expand narrowed areas in your esophagus, stomach, or upper small bowel. A small balloon is inflated, making it easier for food and liquid to pass through. It's safe and effective.

15 services14 patients

Destruction of polyp or growth of large bowel using a flexible endoscope 45388

This procedure involves the removal of a polyp or growth in the large bowel. A flexible endoscope, a thin tube with a camera, is inserted through the rectum to visualize and remove the growth. This helps maintain bowel health and prevent complications.

14 services13 patients

Removal of gallbladder using an endoscope 47562

This procedure, known as endoscopic gallbladder removal, involves a surgeon using a special tool called an endoscope to remove your gallbladder through small incisions. It's typically done to treat gallstones and related complications. It's a less invasive method, often leading to quicker recovery.

13 services13 patients

Insertion of central venous tube with port (5 years or older) 36561

A central venous tube with port is a small, flexible tube inserted into a large vein, usually in the chest. It allows for easy administration of medication, fluids, or blood products over a long period. A port is attached under the skin for easy access. It's safe for individuals aged 5 and above.

12 services12 patients

Hospital Affiliations CMS Care Compare 2

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

Ortonville Area Health Services

Critical Access Hospitals · Ortonville, MN

OwnershipGovernment - Local

CMS Certification Number241342

Location450 Eastvold AveOrtonville, MN 56278 · Big Stone County

Emergency services Birthing friendly

Prairie Lakes Healthcare System, Inc

Acute Care Hospitals · Watertown, SD

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number430005

Location401 9th Avenue NW Post Office Box 1210Watertown, SD 57201 · Codington County

Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 57201 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

$85.21 typical visit price

range $55.52 – $167.23

Typical copayment $21.30 (range $13.88 – $41.80)

Most-billed visit code 99203

Established Patient

$69.20 typical visit price

range $18.08 – $137.08

Typical copayment $17.30 (range $4.52 – $34.27)

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.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

97.75/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored as part of a group practice

Quality

100

Promoting Interoperability

Improvement Activities

Cost

93.34

Referred Medical Equipment & Supplies CMS DME claims 2

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Ostomy skin barrier, with flange (solid, flexible or accordion), extended wear, without built-in convexity, 4 x 4 inches or smaller, each A4409

DME-Orthotic Devices · category DF010N

1 supplier15 claims180 services$5.67 avg. paid by Medicare

Ostomy pouch, drainable; for use on barrier with flange (2 piece system), each A5063

DME-Orthotic Devices · category DF010N

1 supplier15 claims180 services$2.47 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

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 Gregory Gerrish's NPI number?

The NPI number for Gregory Gerrish is 1992097703. It was assigned to this individual provider in the NPPES registry on May 12, 2011.

Where is Gregory Gerrish located?

Gregory Gerrish practices at 401 9th Ave. NW Prairie Lakes Hospital, Watertown, SD 57201. The listed phone number is (605) 882-7000.

What is Gregory Gerrish's specialty?

The primary specialty registered for this NPI is Surgery with taxonomy code 208600000X.

Is Gregory Gerrish enrolled in Medicare?

Yes. Gregory Gerrish 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 Gregory Gerrish's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Gregory Gerrish reassigns Medicare benefits to Prairie Lakes Health Care System Inc (Watertown, SD). 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 Gregory Gerrish's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

What insurance does Gregory Gerrish accept?

Health plans from Avera Health Plans, Sanford Health Plan and Wellmark of South Dakota, Inc. list Gregory Gerrish as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Gregory Gerrish affiliated with any hospitals?

According to CMS data, Gregory Gerrish is affiliated with Ortonville Area Health Services and Prairie Lakes Healthcare System, Inc.

When was this NPI record last updated?

The NPPES record for Gregory Gerrish was last updated on August 17, 2016. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 10 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.