Hayley Chan, MD
Internal Medicine Physician · New Haven, CT
Hayley Chan, MD is an internal medicine physician with a practice address in New Haven, Connecticut, and NPI 1285318345, issued on Jun 9, 2023. Check the license on the Connecticut Medical Examining Board; the Medicare figures below come from public CMS files.
- Name
- Hayley Chan
- Credential
- MD
- Primary taxonomy
- Internal Medicine Physician 207R00000X
- License number
- 125082574 IL
Self-reported in NPPES; status is on the state search - Practice location
- 20 York St, New Haven, CT 06510
- Phone
- (203) 688-4242
- Enumerated
- Jun 9, 2023
- Record last updated
- Jun 15, 2026
- Entity
- Type 1 · individual
8 nearest internal medicine physician records → All 2,623 in Connecticut → Look up another NPI →
Also registered at 20 York St
A shared address usually means a shared clinic or building; it does not show who employs whom.
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Verify Hayley Chan in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersConnecticut Medical Examining BoardCheck the board
- 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
92% fewer Medicare Part D claims than the average internal medicine physician in 2024
257 Medicare Part D claims for 83 beneficiaries, against an average of 3,176 among the 108,855 providers of this specialty who prescribed in Part D. Brand-name drugs were 9% of claims.
Most prescribed
- Famotidine21 claims
- Levetiracetam21 claims
- Lisinopril12 claims
- Prednisone12 claims
- Pantoprazole Sodium11 claims
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.
Hayley Chan among 2,623 internal medicine physician records in Connecticut
Hayley Chan, MD is one of 2,623 internal medicine physician records with a practice address in Connecticut. 81% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2023, is newer than 98% of them.
- NPI issued2023 · 98% of these records are older, under 1% newer
- In a Medicare fileYes · 81% of these records are
- In the CMS Doctors and Clinicians fileNo · 63% of these records are
- Record last updated2026 · 61% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207R00000X and a Connecticut practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
329 internal medicine physician records list a practice address in New Haven
They are 329 of the 9,793 NPPES records with a practice address in New Haven, and 2,623 internal medicine physician records in Connecticut.
All 2,623 in Connecticut → Every provider in New Haven → Internal Medicine Physician nationwide →
The 8 internal medicine physician records with the nearest ZIP codes
- William Becker, M.D.New Haven, CT 065101154427656
- William Crede, MDNew Haven, CT 065101760455984
- Robert Gifford, M.D.New Haven, CT 065101407982242
- Frederick Haeseler, MDNew Haven, CT 065101295862084
- Peter Herbert, MDNew Haven, CT 065101033191465
- Rajlakshmi Krishnamurthy, MDNew Haven, CT 065101568487346
- Chandrika Kumar, M.D.New Haven, CT 065101386645448
- Frank Mongillo, MDNew Haven, CT 065101811917289
Common questions
What is Hayley Chan, MD's NPI number?
Hayley Chan, MD's National Provider Identifier (NPI) is 1285318345, issued on Jun 9, 2023. An NPI identifies a provider in billing; it is not a license.
Where is Hayley Chan, MD located?
The NPPES record lists a practice address at 20 York St, New Haven, CT, 06510. Phone: (203) 688-4242. Providers update this record themselves, so call before visiting.
How can I verify Hayley Chan, MD's license?
Search the Connecticut Medical Examining Board at https://www.elicense.ct.gov/Lookup/LicenseLookup.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Hayley Chan, MD prescribe under Medicare Part D?
In 2024, Hayley Chan, MD had 257 Medicare Part D claims for 83 beneficiaries; the average among internal medicine physician prescribers was 3,176. 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.