Harold Guerrero, DDS
Harold Guerrero, DDS is a provider specialising in General Practice Dentistry in Bay Shore, NY, registered under NPI 1003081811. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
Here is what surrounds this office in Bay Shore, based on OpenStreetMap data collected Sep 4, 2026. Parking is available about 0.24 mi away. A pharmacy sits 0.25 mi from the entrance (CVS Pharmacy), which helps if you leave with a prescription.
Getting here and what is nearby
Parking 902 ft ~4 min
Parking 994 ft ~4 min
Parking 0.24 mi ~5 min
Pharmacy CVS Pharmacy 0.25 mi ~5 min
Convenience 7-Eleven 0.49 mi ~10 min
Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| 043261 | NY | General Practice Dentistry primary |
This provider holds licence 043261 issued in NY. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
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.
What General Practice covers
A general dentist is the primary dental care provider for patients of all ages. The general dentist is responsible for the diagnosis, treatment, management and overall coordination of services related to patients' oral health needs. NUCC Health Care Provider Taxonomy, code 1223G0001X
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.
| NPI | 1003081811 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Apr 23, 2008 |
| Last updated | Apr 23, 2008 |
| Status | Active |
| Sole proprietor | Yes |
| Gender | Male |
| Credential | DDS |
| Practice address |
1355 E 3RD AVE Bay Shore, NY 11706 (631) 968-6524 Fax (631) 968-6524 |
Number check
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 | 0 | 8 | 1 | 8 | 1 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 0 | 8 | 2 | 8 | 2 |
Sum = 49 · next multiple of 10 = 50 · check digit = 1 · actual last digit = 1
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.