Grant Connell Hallock, DO
Critical Care Medicine (Internal Medicine) Physician · Park Ridge, IL
Grant Connell Hallock, DO is a critical care medicine (internal medicine) physician with a practice address in Park Ridge, Illinois, and NPI 1225666357, issued on Apr 1, 2020. Check the license (Illinois 036.166239, as entered in NPPES) on the Illinois Department of Financial and Professional Regulation; the Medicare figures below come from public CMS files.
- Name
- Grant Connell Hallock
- Credential
- DO
- Primary taxonomy
- Critical Care Medicine (Internal Medicine) Physician 207RC0200X
- License number
- 036.166239 IL
Self-reported in NPPES; status is on the state search - Practice location
- 1775 Dempster St, Park Ridge, IL 60068
- Phone
- (847) 723-2210
- Enumerated
- Apr 1, 2020
- Record last updated
- Mar 28, 2024
- Fax
- (847) 723-6987
- Medicare enrollment
- Enrolled (PECOS I20250723003878); accepts Medicare assignment
- Entity
- Type 1 · individual
8 nearest critical care medicine (internal medicine) physician records → All 281 in Illinois → Look up another NPI →
Also registered at 1775 Dempster St
A shared address usually means a shared clinic or building; it does not show who employs whom.
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- Eli Adams, MDStudent in an Organized Health Care Education/Training Program1366292930
- Julie Adams, CRNACertified Registered Nurse Anesthetist1104470426
- Anis Adnani, MDEmergency Medical Services (Emergency Medicine) Physician1356976443
Verify Grant Connell Hallock in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersIllinois Department of Financial and Professional Regulation
Search for license 036.166239Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
96% fewer Medicare Part D claims than the average critical care medicine (internal medicine) physician in 2024
29 Medicare Part D claims, against an average of 696 among the 2,873 providers of this specialty who prescribed in Part D.
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
Bills Medicare through one group practice
- Incare LLCNashua, NH
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Grant Connell Hallock among 281 critical care medicine (internal medicine) physician records in Illinois
Grant Connell Hallock, DO is one of 281 critical care medicine (internal medicine) physician records with a practice address in Illinois. 92% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2020, is newer than 93% of them.
- NPI issued2020 · 93% of these records are older, 4% newer
- In a Medicare fileYes · 92% of these records are
- In the CMS Doctors and Clinicians fileYes · 80% of these records are
- Graduated2020 · median 2008 among the 226 with a school on file
- Record last updated2024 · 22% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RC0200X and a Illinois practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Critical Care Medicine (Internal Medicine) Physician providers in Illinois
There are 281 critical care medicine (internal medicine) physician records in Illinois.
All 281 in Illinois → Every provider in Park Ridge → Critical Care Medicine (Internal Medicine) Physician nationwide →
The 8 critical care medicine (internal medicine) physician records with the nearest ZIP codes
- Jared Brooks, DOPark Ridge, IL 600681205396298
- Kyle Henn, MDPark Ridge, IL 600681902431174
- Clayton Johnson, DOPark Ridge, IL 600681760185904
- Mae LeefPark Ridge, IL 600681538862727
- Nikolina Madjer, MDPark Ridge, IL 600681427798883
- Scott Moore, D.O.Park Ridge, IL 600681619356961
- Thomas Riney, MD, FAAEM, FACEPPark Ridge, IL 600681225567571
- Jason Ross, MDPark Ridge, IL 600681205496312
Common questions
What is Grant Connell Hallock, DO's NPI number?
Grant Connell Hallock, DO's National Provider Identifier (NPI) is 1225666357, issued on Apr 1, 2020. An NPI identifies a provider in billing; it is not a license.
Where is Grant Connell Hallock, DO located?
The NPPES record lists a practice address at 1775 Dempster St, Park Ridge, IL, 60068. Phone: (847) 723-2210. Providers update this record themselves, so call before visiting.
How can I verify Grant Connell Hallock, DO's license?
NPPES lists Illinois license number 036.166239, as entered by the provider. Search the Illinois Department of Financial and Professional Regulation at https://idfpr.illinois.gov/checklicense.html. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Grant Connell Hallock, DO prescribe under Medicare Part D?
In 2024, Grant Connell Hallock, DO had 29 Medicare Part D claims; the average among critical care medicine (internal medicine) physician prescribers was 696. Part D covers Medicare prescriptions only.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.