Merrill Littleberry, LCSW, LCDC, CCM
Merrill Littleberry, LCSW, LCDC, CCM is an Addiction (Substance Use Disorder) Counselor in Fort Worth, TX, registered under NPI 1649235060. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty. 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 4200 SOUTH FWY SUITE 424, Fort Worth, TX 76115. 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 |
|---|---|---|
| 9615 | TX | Addiction (Substance Use Disorder)… primary |
| 28682 | TX | Clinical Social Worker |
This provider holds licence 9615 issued in TX. 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 - Clinical Social Worker
- PAC ID
- 6901829993
Enrolled in Medicare 2 times, across 2 states:
| State | Enrollment ID | Provider type |
|---|---|---|
| Texas | I20060104001010 | Practitioner - Clinical Social Worker |
| Oregon | I20230828002697 | Practitioner - Clinical Social Worker |
Medicare enrolment is recorded as approved under the provider type Practitioner - Clinical Social Worker. There are 2 separate enrolment records across 2 states (TX, OR). 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 Addiction (Substance Use Disorder) covers
Definition to come... NUCC Health Care Provider Taxonomy, code 101YA0400X
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.
| Code | Specialty | Licence | State | |
|---|---|---|---|---|
| 101YA0400X | Addiction (Substance Use Disorder) Counselor Addiction (Substance Use Disorder) | 9615 | TX | primary |
| 1041C0700X | Clinical Social Worker Clinical | 28682 | TX |
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 | 1649235060 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Apr 19, 2006 |
| Last updated | Feb 24, 2026 |
| Status | Active |
| Sole proprietor | Yes |
| Gender | Female |
| Credential | LCSW, LCDC, CCM |
| Practice address |
4200 SOUTH FWY SUITE 424 Fort Worth, TX 76115 (817) 920-9321 Fax (817) 920-9336 |
| Mailing address |
4200 SOUTH FWY STE 424 Fort Worth, TX 76115 |
| Other identifiers |
177933201
· Medicaid (TX) 51mx · Other (TX) 560613 · Other (TX) 63003 · Other (TX) |
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 | 6 | 4 | 9 | 2 | 3 | 5 | 0 | 6 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 6 | 8 | 9 | 4 | 3 | 1 | 0 | 3 |
Sum = 60 · next multiple of 10 = 60 · check digit = 0 · actual last digit = 0
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.