T THIEU OD LLC
T THIEU OD LLC is an organization registered with the National Plan and Provider Enumeration System (NPPES) under NPI 1003181421, based in Chalfont, PA. It is classified under Optometrist.
Getting there
Here is what surrounds this office in Chalfont, based on OpenStreetMap data collected Sep 10, 2026. Parking is available about 0.27 mi away. A pharmacy sits 0.47 mi from the entrance (CVS Pharmacy), which helps if you leave with a prescription.
Getting here and what is nearby
Parking 0.25 mi ~5 min
Parking 0.25 mi ~5 min
Parking 0.27 mi ~6 min
Restaurant Chalfont Family Restaurant 0.27 mi ~6 min
Restaurant Pop! Inn 0.32 mi ~7 min
Restaurant Manhattan Bagel 0.34 mi ~7 min
5 East Butler Avenue, Chalfont 18914
Mo-Su 06:00-14:00
Pharmacy CVS Pharmacy 0.47 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 |
|---|---|---|
| OEG001198 | PA | Optometrist primary |
This provider holds licence OEG001198 issued in PA. 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 Optometrist covers
Doctors of optometry (ODs) are the primary health care professionals for the eye. Optometrists examine, diagnose, treat, and manage diseases, injuries, and disorders of the visual system, the eye, and associated structures as well as identify related systemic conditions affecting the eye. An optometrist has completed pre-professional undergraduate education in a college or university and four years of professional education at a college of optometry, leading to the doctor of optometry (O.D.) degree. Some optometrists complete an optional residency in a specific area of practice. Optometrists are eye health care professionals state-licensed to diagnose and treat diseases and disorders of the eye and visual system. NUCC Health Care Provider Taxonomy, code 152W00000X
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-2 identifies an organization — a clinic, hospital, group practice, laboratory, or supplier. Individual clinicians working there hold their own NPI-1 numbers separately, so a bill may reference both.
| NPI | 1003181421 valid check digit |
|---|---|
| Entity type | Organization (NPI-2) |
| Enumeration date | Mar 19, 2012 |
| Last updated | Mar 16, 2015 |
| Status | Active |
| Practice address |
3425 LIMEKILN PIKE SUITE 2 Chalfont, PA 18914 (215) 997-0411 |
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 | 1 | 8 | 1 | 4 | 2 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 0 | 0 | 3 | 2 | 8 | 2 | 4 | 4 |
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.