Dr. Gregory Mark Gerrish, MD
- Medicare services, 2024
- 432
- Medicare patients, 2026
- 296
- Part D claims, 2026
- 482
- MIPS score, 2026
- 95
- Hospital affiliations
- 2
- Practice address
- 401 9th Avenue NW Post Office Box 1210, Watertown, SD 57201
- Practice phone
- Call (605) 882-7000
- Professional email
- Get professional email
- Personal email
- Get personal email
- Mobile number
- Get mobile number
Primary practice
Find Dr. Gerrish's professional email, personal email and mobile number
Dmand AI checks each channel through healthcare-specific waterfall enrichment. See what is on file with a free account, with practice phones, licenses and affiliations.
Dr. Gregory Mark Gerrish is a general surgeon in Watertown, South Dakota
Dr. Gerrish practices at Sanford Health Watertown in Watertown, South Dakota, part of Sanford Health.
Dr. Gerrish's NPI, 1992097703, was assigned on May 12, 2011. Dr. Gerrish graduated from Sanford School of Medicine of University of South Dakota in 2011. Dr. Gerrish holds South Dakota license 10080.
- NPI
- 1992097703NPI Registry (opens in a new tab)
- Medicare PAC ID
- 8527363712
- NPI enumeration date
- May 12, 2011
- NPI status
- Active
- Accepts Medicare assignment
- Yes
- Practice phone
- (605) 882-7000
- Professional email
- Get email
- Personal email
- Get email
- Mobile number
- Get number
- Sex
- Male
- Estimated age
- 41
- Medical school graduation
- 2011
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; Dmand AI Affiliation Data; and Doctors and Clinicians National Downloadable File (CMS)
Dr. Gregory Mark Gerrish practices at Sanford Health Watertown in Watertown, South Dakota
Dr. Gerrish's primary practice is Sanford Health Watertown, at 401 9th Avenue NW Post Office Box 1210, Watertown, SD 57201 in Codington County. The practice phone is (605) 882-7000.
- Sanford Health Watertown401 9th Avenue NW Post Office Box 1210, Watertown, SD 57201 · Codington CountyPhone(605) 882-7000
Source: Dmand AI Affiliation Data
Dr. Gregory Mark Gerrish is affiliated with 4 sites of care and 1 medical group
Dr. Gerrish's primary practice is Sanford Health Watertown in Watertown, South Dakota, part of Sanford Health. Dr. Gerrish is also affiliated with Ortonville Hospital. The medical group on file is Prairie Lakes Healthcare System. Dmand AI also links Dr. Gerrish to 1 more home health agency and 1 hospice, each named with a free account. Dr. Gerrish's employer is on file too: a hospital.
Sources: Dmand AI Affiliation Data; and Dmand AI Org Hierarchy Data
Dmand AI tracks the EHR system at Dr. Gregory Mark Gerrish's practice
Dmand AI tracks the electronic health record (EHR) system at each site where Dr. Gerrish practices, 4 sites in all. Vendor and product names are available with a free account.
| Site | EHR vendor and product |
|---|---|
| Sanford Health Watertown | Available with a free account |
| +3 more affiliated sites | Available with a free account |
Source: Dmand AI Technology Install Data
For health IT teams
Dmand AI maps EHR vendors, IT decision makers and buying committees across Sanford Health and 6.2K+ hospitals, with verified contacts in the same login.
Dr. Gregory Mark Gerrish is one of 105 general surgeons in South Dakota
Surgery is Dr. Gerrish's primary specialty in the NPI Registry, under taxonomy code 208600000X. Dr. Gerrish is licensed in South Dakota.
Specialties and state licenses
- Surgery, South DakotaPrimary
General surgeons near Dr. Gerrish
Counts of general surgeons with a Dmand AI profile, by place and practice. Each opens the list.
Sources: NPPES NPI Registry (CMS); Dmand AI Professional Profile Data; and Dmand AI Peer Benchmarks
Dr. Gregory Mark Gerrish billed Medicare for 432 services in 2024
CMS data shows 432 Medicare services from Dr. Gerrish across 15 procedure codes in 2024, for 296 Medicare patients. Medicare paid $48,274 for them. Every service was in a facility, such as a hospital, rather than an office.
Dr. Gerrish's Medicare services by type, 2024
- Surgery241
- Office and hospital visits151
- Other services40
Dr. Gerrish compared with the South Dakota median for general surgeons, 2024
- Dr. Gerrish
- South Dakota median
- Medicare services
- 432vs 1782.4 times
- Medicare patients
- 296vs 16283% above
- Part D claims
- 367vs 3610.2 times
Medians across 105 general surgeons in South Dakota with Dmand AI profiles that report each measure.
Dr. Gerrish's most billed Medicare procedure codes, 2024
CMS publishes codes billed for 11 or more Medicare patients. Each label is the code family; CPT descriptions are licensed by the AMA.
Need commercial claims for Dr. Gerrish?
Medicare shows one payer. Book a meeting to get commercial claims data for Dr. Gerrish and other general surgeons in South Dakota.
Sources: Medicare Physician & Other Practitioners - by Provider and Service (CMS), 2024 data; and Dmand AI Peer Benchmarks
Dr. Gregory Mark Gerrish treated 296 Medicare patients in 2026, average age 72
CMS counts 296 Medicare patients who saw Dr. Gerrish in 2026. The largest group is 65 to 74, with 179 patients. 72% of them have high cholesterol, and 68% have high blood pressure. 10% are also on Medicaid. Their average risk score is 1.14, where 1.00 is the Medicare average.
Across all payers, Dmand AI patient panel data puts Dr. Gerrish's median patient age at 72, with 47% women.
Dr. Gerrish's Medicare patients by age, 2026
Dr. Gerrish's Medicare patients by sex, 2026
- Women14950%
- Men14750%
Chronic conditions among Dr. Gerrish's Medicare patients, 2026
- High cholesterol72%
- High blood pressure68%
- Arthritis38%
- Diabetes31%
- Chronic kidney disease28%
- Ischemic heart disease27%
- Mood disorders24%
- Depression23%
Share of Medicare patients with each condition. A patient can have several.
Dr. Gerrish's patients across all payers
Dmand AI patient panel data covers Medicare, Medicaid and commercial patients.
Patient panel by age, all payers
Median age 72
Patient panel by sex, all payers
- Women47%
- Men53%
Sources: Dmand AI Patient Panel Data; and Medicare Physician & Other Practitioners - by Provider (CMS), 2026 data
Dr. Gregory Mark Gerrish wrote 482 Medicare Part D claims in 2026
In 2026, Dr. Gerrish wrote 482 Medicare Part D claims for 312 patients. 93% of them were for generic drugs. CMS names the drug for 367 of them, across 7 drugs with 11 or more claims each, at $4,164 in total drug cost.
Dr. Gerrish's Part D claims by kind of drug, 2026
- Generic450 claims93%
- Brand-name32 claims7%
Dr. Gerrish's most prescribed drugs by claims, 2024
CMS names a drug when it has 11 or more claims. Share is of the claims for drugs CMS names.
Drug classes CMS tracks in Dr. Gerrish's Part D claims, 2026
- Opioids10%49 of 482 claims
- Antibiotics10%50 of 482 claims
Share of all Part D claims for each drug class CMS reports on. Classes with no claims are left out.
Sources: Medicare Part D Prescribers - by Provider and Drug (CMS), 2024 data, released May 6, 2026; and Medicare Part D Prescribers - by Provider (CMS), 2026 data
Dr. Gregory Mark Gerrish scored 95 out of 100 in Medicare's MIPS program for 2026
CMS publishes a Merit-based Incentive Payment System (MIPS) score of 95 out of 100 for Dr. Gerrish for performance year 2026, reported as part of a group. Dr. Gerrish accepts Medicare assignment, so Medicare's approved amount is taken as full payment. CMS counts 84 procedures of colonoscopy by Dr. Gerrish, more than 76% of the clinicians it reports for that procedure.
- Accepts Medicare assignment
- Yes
Dr. Gerrish's MIPS scores, performance year 2026
- 95of 100Final score
- 100of 100Quality
- 96of 100Promoting Interoperability
- 40of 100Improvement Activities
- 85of 100Cost
Each score is out of 100. The final score weighs the categories CMS scored for this clinician.
Where Dr. Gerrish ranks in Medicare procedure volume
- Upper gastrointestinal (GI) endoscopy for acid reflux
- 73rd percentile85 procedures
- Colonoscopy
- 76th percentile84 procedures
CMS ranks each clinician against every clinician it reports for the same procedure category.
Hernia repair (minimally invasive): 1 to 10 procedures (CMS shows small counts as a range)
Hernia repair - groin (open): 1 to 10 procedures (CMS shows small counts as a range)
Removal of tissue: 1 to 10 procedures (CMS shows small counts as a range)
Removal or shaving of skin growth: 1 to 10 procedures (CMS shows small counts as a range)
Sources: Doctors and Clinicians National Downloadable File (CMS); Clinician Public Reporting: Overall MIPS Performance (CMS), 2026 data; and Doctors and Clinicians Utilization Data (CMS)
For MedTech and pharma teams
Filter 7.4M+ HCPs by Medicare procedures, Part D drugs and Open Payments history, then reach them with verified contacts in one login.
Dr. Gregory Mark Gerrish received $329 in industry payments from 2024 to 2025
CMS Open Payments shows 12 general payments to Dr. Gerrish from 7 drug and device companies from 2024 to 2025. Food and beverage make up the largest share, 100% of the total. Organogenesis Inc. paid the most, $177.
General payments to Dr. Gerrish by program year, 2024 to 2025
Companies that paid Dr. Gerrish the most, 2024 to 2025
Share is of all general payments to this clinician.
Source: Open Payments (CMS), 2025 data, released July 7, 2026
Dr. Gregory Mark Gerrish graduated from Sanford School of Medicine of University of South Dakota
Dr. Gerrish graduated from Sanford School of Medicine of University of South Dakota in 2011.
- Medical school
Source: Dmand AI Professional Profile Data
Sources for Dr. Gregory Mark Gerrish's profile data
| Data on this page | Source |
|---|---|
| NPI, name, sex, specialty and licenses | NPPES NPI Registry (CMS) (opens in a new tab)Dmand AI Professional Profile Data |
| Practice locations and phone | Dmand AI Affiliation Data |
| Primary practice, affiliations and health system | Dmand AI Affiliation DataDmand AI Org Hierarchy Data |
| Medicare services and procedure codes | Medicare Physician & Other Practitioners - by Provider and Service (CMS) (opens in a new tab) |
| State medians for the same specialty | Dmand AI Peer Benchmarks |
| Medicare patients and the all-payer patient panel | Dmand AI Patient Panel DataMedicare Physician & Other Practitioners - by Provider (CMS) (opens in a new tab) |
| Part D prescribing | Medicare Part D Prescribers - by Provider and Drug (CMS) (opens in a new tab)Medicare Part D Prescribers - by Provider (CMS) (opens in a new tab) |
| MIPS scores, telehealth, assignment and procedure percentiles | Doctors and Clinicians National Downloadable File (CMS) (opens in a new tab)Clinician Public Reporting: Overall MIPS Performance (CMS) (opens in a new tab)Doctors and Clinicians Utilization Data (CMS) (opens in a new tab) |
| Industry payments | Open Payments (CMS) (opens in a new tab) |
| Training, board certification and memberships | Dmand AI Professional Profile Data |
| EHR at each practice site | Dmand AI Technology Install Data |
| Similar physicians | Dmand AI Affiliation Data |
Data last refreshed October 2026Report an inaccuracyRemove my information
FAQ
Frequently asked questions about Dr. Gregory Mark Gerrish
Spotted something out of date? Email hello@dmand.ai and we will check the record. Contact details live in the free trial.
What is Dr. Gregory Mark Gerrish's NPI number?
Dr. Gregory Mark Gerrish's NPI number is 1992097703. It was assigned on May 12, 2011, and it is active in the NPI Registry.
What kind of doctor is Dr. Gregory Mark Gerrish?
Dr. Gregory Mark Gerrish is a general surgeon in Watertown, South Dakota. The primary specialty in the NPI Registry is Surgery Physician (taxonomy code 208600000X).
Where does Dr. Gregory Mark Gerrish practice?
Dr. Gerrish practices at 401 9th Avenue NW Post Office Box 1210, Watertown, SD 57201. Dr. Gerrish's primary practice is Sanford Health Watertown in Watertown, South Dakota, part of Sanford Health. Dmand AI also links Dr. Gerrish to 1 home health agency and 1 hospice, and a free account names each one.
What is Dr. Gregory Mark Gerrish's office phone number?
The practice phone on file for Dr. Gerrish is (605) 882-7000. Dmand AI also checks direct phone and mobile numbers, available with a free account.
What is Dr. Gregory Mark Gerrish's email address?
Dmand AI checks professional and personal email addresses for Dr. Gerrish through healthcare-specific waterfall enrichment. They are available with a free Dmand AI account.
What is Dr. Gregory Mark Gerrish's medical license number?
Dr. Gerrish holds South Dakota license 10080, one of 2 state licenses on file.
Which hospitals is Dr. Gregory Mark Gerrish affiliated with?
Dr. Gerrish practices at Sanford Health Watertown in Watertown, South Dakota. Dr. Gerrish is also affiliated with Ortonville Hospital.
What medical group is Dr. Gregory Mark Gerrish part of?
Dr. Gerrish is linked to Prairie Lakes Healthcare System.
Who employs Dr. Gregory Mark Gerrish?
Dmand AI has Dr. Gerrish's employer on file: a hospital. The organization's name is available with a free Dmand AI account.
Who does Dr. Gregory Mark Gerrish practice with?
Dmand AI links 85 HCPs to Dr. Gerrish's primary medical group, 3 of them general surgeons. A free account lists them, with verified contacts.
Show 9 more questionsShow fewer questions
Does Dr. Gregory Mark Gerrish accept Medicare?
Yes. CMS data shows Dr. Gerrish billed Medicare for 432 services in 2024, and Dr. Gerrish accepts Medicare assignment.
What is Dr. Gregory Mark Gerrish's MIPS score?
Dr. Gerrish's MIPS final score for performance year 2026 is 95 out of 100, reported as part of a group.
How many Medicare patients does Dr. Gregory Mark Gerrish see?
CMS counts 296 Medicare patients who saw Dr. Gerrish in 2026, with an average age of 72.
What services does Dr. Gregory Mark Gerrish bill to Medicare?
In 2024, Dr. Gerrish's most billed Medicare services were office visit, established patient (99213), surgery: digestive system (43239) and surgery: digestive system (45385).
Where did Dr. Gregory Mark Gerrish go to medical school?
Dr. Gerrish graduated from Sanford School of Medicine of University of South Dakota in 2011.
What drugs does Dr. Gregory Mark Gerrish prescribe most?
In 2024 Medicare Part D data, Dr. Gerrish's most prescribed drugs by claims were Gavilyte-G, Omeprazole and Tramadol HCl.
Has Dr. Gregory Mark Gerrish received payments from drug or device companies?
CMS Open Payments shows $329 in general payments to Dr. Gerrish from 7 companies from 2024 to 2025. The largest total came from Organogenesis Inc.
How long has Dr. Gregory Mark Gerrish been practicing?
Dr. Gerrish graduated from medical school in 2011, 15 years ago.
What EHR does Dr. Gregory Mark Gerrish's practice use?
Dmand AI tracks the EHR system at Sanford Health Watertown and at 3 more affiliated sites. The vendor and product are available with a free Dmand AI account.
Selling to surgery practices?
See general surgeons in South Dakota by site of care and group
Find the practices, groups and hospitals they work with, and the right people to contact at each.
- 30 days free
- Self-serve
- No credit card