Mackenzie Callahan
Mackenzie Callahan is a Clinical Psychologist in Chelsea, MI, registered under NPI 1366288698. 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 350 N MAIN ST STE 220, Chelsea, MI 48118. 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 |
|---|---|---|
| 6301019746 | MI | Clinical Psychologist primary |
This provider holds licence 6301019746 issued in MI. 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 Clinical covers
A psychologist who provides continuing and comprehensive mental and behavioral health care for individuals and families; consultation to agencies and communities; training, education and supervision; and research-based practice. It is a specialty in breadth -- one that is broadly inclusive of severe psychopathology -- and marked by comprehensiveness and integration of knowledge and skill from a broad array of disciplines within and outside of psychology proper. The scope of clinical psychology encompasses all ages, multiple diversities and varied systems. NUCC Health Care Provider Taxonomy, code 103TC0700X
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 | 1366288698 valid check digit |
|---|---|
| Entity type | Individual (NPI-1) |
| Enumeration date | Jul 5, 2024 |
| Last updated | Sep 5, 2025 |
| Status | Active |
| Sole proprietor | Yes |
| Practice address |
350 N MAIN ST STE 220 Chelsea, MI 48118 (734) 433-5100 |
| Mailing address |
13098 SPECKLEDWOOD DR Dewitt, MI 48820 |
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 | 3 | 6 | 6 | 2 | 8 | 8 | 6 | 9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Doubled? | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 | — | ×2 |
| Value | 8 | 0 | 8 | 8 | 0 | 2 | 3 | 3 | 6 | 4 | 8 | 7 | 6 | 9 |
Sum = 72 · next multiple of 10 = 80 · check digit = 8 · actual last digit = 8
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.