Individual provider

Christina Grassi, M.D.

Ophthalmology Physician

Christina Grassi, M.D. is an Ophthalmology Physician in Cambridge, MA, registered under NPI 1306228515.

Getting there

The practice address on file is 330 MT AUBURN ST MOUNT AUBURN HOSPITAL, Cambridge, MA 02138. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

330 MT AUBURN ST MOUNT AUBURN HOSPITAL, Cambridge, MA 02138 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
286348 NY Ophthalmology Physician primary
264380 MA Ophthalmology Physician

Licences are recorded in 2 states: NY, MA. 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: Massachusetts and New York. The practice address on file is in Cambridge, MA, 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.

MA Massachusetts practice address
Licence
264380
Specialty
Ophthalmology Physician
Verify with the MA board →
NY New York
Licence
286348
Specialty
Ophthalmology Physician
Verify with the NY 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 Ophthalmology covers

An ophthalmologist has the knowledge and professional skills needed to provide comprehensive eye and vision care. Ophthalmologists are medically trained to diagnose, monitor and medically or surgically treat all ocular and visual disorders. This includes problems affecting the eye and its component structures, the eyelids, the orbit and the visual pathways. In so doing, an ophthalmologist prescribes vision services, including glasses and contact lenses. NUCC Health Care Provider Taxonomy, code 207W00000X
Allopathic & Osteopathic Physicians Ophthalmology

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
207W00000X Ophthalmology Physician 286348 NY primary
207W00000X Ophthalmology Physician 264380 MA

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.

NPI1306228515 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateJun 24, 2015
Last updatedFeb 12, 2020
StatusActive
Sole proprietorNo
CredentialM.D.
Practice address 330 MT AUBURN ST
MOUNT AUBURN HOSPITAL
Cambridge, MA 02138
(617) 492-3500
Mailing address POST OFFICE BOX 202
Winchester, MA 01890
The last update on file is Feb 12, 2020. Providers are only required to update NPPES when their information changes, so an older date does not necessarily mean the details are wrong — but it is worth a quick call before you travel.

Number check

1306228515 passes the NPI check digit test The final digit 5 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 3 0 6 2 2 8 5 1
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 3 0 6 4 2 7 5 2

Sum = 55 · next multiple of 10 = 60 · check digit = 5 · actual last digit = 5

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 1306228515?
NPI 1306228515 is the National Provider Identifier assigned to Christina Grassi, M.D. in Cambridge, MA. 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 Ophthalmology Physician cover?
An ophthalmologist has the knowledge and professional skills needed to provide comprehensive eye and vision care. Ophthalmologists are medically trained to diagnose, monitor and medically or surgically treat all ocular and visual disorders. This includes problems affecting the eye and its component structures, the…
How do I contact Christina Grassi, M.D.?
The phone number on file with NPPES is (617) 492-3500, last updated Feb 12, 2020. 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 1306228515 a valid number?
Yes. 1306228515 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.