Individual provider

Justin Grammy, DO

Internal Medicine Physician Hospitalist Physician Medicare enrolled

Justin Grammy, DO is a Hospitalist Physician in San Luis Obispo, CA, registered under NPI 1003254483. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

Here is what surrounds this office in San Luis Obispo, based on OpenStreetMap data collected Sep 14, 2026. Parking is available about 0.51 mi away. The nearest transit stop is 0.38 mi away, served by Monterey & Grand. If you arrive early, there is a coffee shop 0.28 mi away.

1428 PHILLIPS LN STE 203, San Luis Obispo, CA 93401 Open in Google Maps →

Getting here and what is nearby

Parking 137 ft ~1 min
Parking 199 ft ~1 min
Coffee Outspoken Cafe 0.20 mi ~5 min

1422 Monterey Street

Website

Directions in Google Maps →

Restaurant Frank's Famous Hot Dogs 0.20 mi ~4 min
Restaurant Ziggy's 0.21 mi ~5 min

594 California Boulevard, San Luis Obispo 93405

Mo-Su 11:00-21:00

+1-805-439-4399

Website

Directions in Google Maps →

Restaurant Poke Chef 0.21 mi ~5 min

580 California Boulevard, San Luis Obispo 93405

Mo-Sa 11:00-21:00; Su 11:30-21:00

+1-805-996-0038

Website

Directions in Google Maps →

Hotel Petit Soleil, Bed and Breakfast 0.23 mi ~5 min
Coffee Alma Cafe 0.24 mi ~5 min

1531 Monterey Street

Directions in Google Maps →

Hotel Lamplighter Inn & Suites 0.24 mi ~5 min
Hotel Sunbeam Motel 0.26 mi ~6 min
Convenience 7-Eleven 0.27 mi ~6 min

1301 Monterey Street, San Luis Obispo 93401

24/7

+1 805-544-3975

Website

Directions in Google Maps →

Coffee Kaffein Coffee Company 0.28 mi ~6 min

1242 Monterey Street, San Luis Obispo 93401

Mo-Su 07:00-15:00

Directions in Google Maps →

Convenience 7-Eleven 0.28 mi ~6 min

552 California Boulevard, San Luis Obispo 93405-1905

+1 805-541-0260

Website

Directions in Google Maps →

Convenience Slo Asian Market 0.29 mi ~6 min

1255 Monterey Street

Mo-Sa 10:00-18:00

+1-805-544-8599

Directions in Google Maps →

Transit Grand & Wilson 0.31 mi ~7 min
Gas station University Gas 0.31 mi ~7 min
Transit Grand & Abbott 0.34 mi ~7 min
Transit Monterey & Grand 0.38 mi ~8 min
Gas station Speedway Express 0.41 mi ~9 min
Gas station Conserv Fuel 0.44 mi ~9 min
Grocery Smart & Final Extra! 0.45 mi ~10 min

1321 Johnson Avenue, San Luis Obispo

+1-805-596-0867

Directions in Google Maps →

Parking 0.51 mi ~11 min
OpenStreetMap via Overpass · ODbL 800 m radius Updated Sep 14, 2026

Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.

Credentials and Medicare

State licence
LicenceStateSpecialty
OS018634 PA Internal Medicine Physician
16620 CA Internal Medicine Physician
16620 CA Hospitalist Physician primary

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

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Internal Medicine
PAC ID
3274804752
Enrollment ID
I20180901000074

Medicare enrolment is recorded as approved under the provider type Practitioner - Internal Medicine. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 2 states

This provider holds licences in 2 states: California and Pennsylvania. The practice address on file is in San Luis Obispo, 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.

CA California practice address
Licence
16620
Specialty
Internal Medicine Physician
Verify with the CA board →
PA Pennsylvania
Licence
OS018634
Specialty
Internal Medicine Physician
Verify with the PA 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 Hospitalist covers

Hospitalists are physicians whose primary professional focus is the general medical care of hospitalized patients. Their activities include patient care, teaching, research, and leadership related to Hospital Medicine. The term 'hospitalist' refers to physicians whose practice emphasizes providing care for hospitalized patients. NUCC Health Care Provider Taxonomy, code 208M00000X
Allopathic & Osteopathic Physicians Hospitalist

All registered taxonomy codes

This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207R00000X Internal Medicine Physician OS018634 PA
207R00000X Internal Medicine Physician 16620 CA
208M00000X Hospitalist Physician 16620 CA primary

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.

NPI1003254483 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateJun 7, 2013
Last updatedNov 17, 2021
StatusActive
Sole proprietorNo
GenderMale
CredentialDO
Practice address 1428 PHILLIPS LN STE 203
San Luis Obispo, CA 93401
(805) 543-4407
Fax (805) 543-4587
Mailing address PO BOX 12460
San Luis Obispo, CA 93406
The last update on file is Nov 17, 2021. 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

1003254483 passes the NPI check digit test The final digit 3 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 0 0 3 2 5 4 4 8
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 0 0 3 4 5 8 4 7

Sum = 57 · next multiple of 10 = 60 · check digit = 3 · actual last digit = 3

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 1003254483?
NPI 1003254483 is the National Provider Identifier assigned to Justin Grammy, DO in San Luis Obispo, 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 Hospitalist Physician cover?
Hospitalists are physicians whose primary professional focus is the general medical care of hospitalized patients. Their activities include patient care, teaching, research, and leadership related to Hospital Medicine. The term 'hospitalist' refers to physicians whose practice emphasizes providing care for…
How do I contact Justin Grammy, DO?
The phone number on file with NPPES is (805) 543-4407, last updated Nov 17, 2021. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Justin Grammy, DO accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Where do I park when visiting Justin Grammy, DO?
Parking is about 0.51 mi from the office. The closest transit stop is 0.38 mi away, on Monterey & Grand. Distances are straight-line estimates from OpenStreetMap, so walking routes may be slightly longer.
Is NPI 1003254483 a valid number?
Yes. 1003254483 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.