David Tong
David Tong is a Professional Counselor in Olney, MD, registered under NPI 1174194005. NPPES records them as a sole proprietor, meaning the practice is not incorporated as a separate legal entity.
Getting there
The practice address on file is 4817 WILLOW STEAD DR, Olney, MD 20832. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.
Credentials and Medicare
| Licence | State | Specialty |
|---|---|---|
| LC13969 | MD | Professional Counselor primary |
This provider holds licence LC13969 issued in MD. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.
- Status
- Approved
- Provider type
- Practitioner - Mental Health Counselor
- PAC ID
- 0244675254
Enrolled in Medicare 2 times, across 2 states:
| State | Enrollment ID | Provider type |
|---|---|---|
| Maryland | I20240229002907 | Practitioner - Mental Health Counselor |
| District of Columbia | I20240229003283 | Practitioner - Mental Health Counselor |
Medicare enrolment is recorded as approved under the provider type Practitioner - Mental Health Counselor. There are 2 separate enrolment records across 2 states (MD, DC). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. 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.
What Professional covers
Definition to come... NUCC Health Care Provider Taxonomy, code 101YP2500X
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 | 1174194005 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 1, 2021 |
| Last updated | Jul 7, 2023 |
| Status | Active |
| Sole proprietor | Yes |
| Practice address |
4817 WILLOW STEAD DR Olney, MD 20832 (301) 842-7431 |
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 | 1 | 7 | 4 | 1 | 9 | 4 | 0 | 0 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 1 | 5 | 4 | 2 | 9 | 8 | 0 | 0 |
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.