Individual provider

Chelsea Takamatsu, MD

Nephrology Physician Internal Medicine Physician

Chelsea Takamatsu, MD is a Nephrology Physician in Palo Alto, CA, registered under NPI 1861013096. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

The practice address on file is 300 PASTEUR DR, Palo Alto, CA 94305. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

300 PASTEUR DR, Palo Alto, CA 94305 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
195259 CA Nephrology Physician primary
R78078 AZ Internal Medicine Physician

Licences are recorded in 2 states: CA, AZ. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)

This NPI does not appear in the PECOS Medicare enrolment file. Providers who do not bill Medicare — or who bill only through a group's enrolment — will not appear here. It is not a sign of any problem with the registration.

Licensed in 2 states

This provider holds licences in 2 states: Arizona and California. The practice address on file is in Palo Alto, CA, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

AZ Arizona
Licence
R78078
Specialty
Internal Medicine Physician
Verify with the AZ board →
CA California practice address
Licence
195259
Specialty
Nephrology Physician
Verify with the CA board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Nephrology covers

An internist who treats disorders of the kidney, high blood pressure, fluid and mineral balance and dialysis of body wastes when the kidneys do not function. This specialist consults with surgeons about kidney transplantation. NUCC Health Care Provider Taxonomy, code 207RN0300X
Allopathic & Osteopathic Physicians Internal Medicine Nephrology

All registered taxonomy codes

This provider registers 2 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207RN0300X Nephrology Physician Nephrology 195259 CA primary
207R00000X Internal Medicine Physician R78078 AZ

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1861013096 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateApr 28, 2020
Last updatedJul 15, 2024
StatusActive
Sole proprietorNo
CredentialMD
Practice address 300 PASTEUR DR
Palo Alto, CA 94305
(650) 721-6680
Fax (539) 265-5945
Other identifiers 61172 · Other (AZ)
195259 · Other (CA)
This record was updated on Jul 15, 2024, which is recent enough that the contact details are likely still accurate.

Number check

1861013096 passes the NPI check digit test The final digit 6 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 8 6 1 0 1 3 0 9
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 8 3 1 0 1 6 0 9

Sum = 54 · next multiple of 10 = 60 · check digit = 6 · actual last digit = 6

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1861013096?
NPI 1861013096 is the National Provider Identifier assigned to Chelsea Takamatsu, MD in Palo Alto, CA. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Nephrology cover?
An internist who treats disorders of the kidney, high blood pressure, fluid and mineral balance and dialysis of body wastes when the kidneys do not function. This specialist consults with surgeons about kidney transplantation.
How do I contact Chelsea Takamatsu, MD?
The phone number on file with NPPES is (650) 721-6680, last updated Jul 15, 2024. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Is NPI 1861013096 a valid number?
Yes. 1861013096 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.