Individual provider

Mary Ellen Lemieux, J.D., LCSW

Clinical Social Worker Medicare enrolled

Mary Ellen Lemieux, J.D., LCSW is a provider specialising in Clinical Social Worker in Palo Alto, CA, registered under NPI 1134517600. 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 518 HAMILTON AVE, Palo Alto, CA 94301. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

518 HAMILTON AVE, Palo Alto, CA 94301 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
73557 CA Clinical Social Worker primary
11557310-3501 UT Clinical Social Worker
09926365 CO Clinical Social Worker

Licences are recorded in 3 states: CA, UT, CO. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Clinical Social Worker
PAC ID
0840735056

Medicare enrolment is recorded as approved under the provider type Practitioner - Clinical Social Worker. This means the provider is enrolled to bill Medicare, though it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 3 states

This provider holds licences in 3 states: California, Colorado and Utah. The practice address on file is in Palo Alto, CA, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

CA California practice address
Licence
73557
Specialty
Clinical Social Worker
Verify with the CA board →
CO Colorado
Licence
09926365
Specialty
Clinical Social Worker
Verify with the CO board →
UT Utah
Licence
11557310-3501
Specialty
Clinical Social Worker
Verify with the UT board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Clinical covers

A social worker who holds a master's or doctoral degree in social work from an accredited school of social work in addition to at least two years of post-master's supervised experience in a clinical setting. The social worker must be licensed, certified, or registered at the clinical level in the jurisdiction of practice. A clinical social worker provides direct services, including interventions focused on interpersonal interactions, intrapsychic dynamics, and life management issues. Clinical social work services are based on bio-psychosocial perspectives. Services consist of assessment, diagnosis, treatment (including psychotherapy and counseling), client-centered advocacy, consultation, evaluation, and prevention of mental illness, emotional, or behavioral disturbances. NUCC Health Care Provider Taxonomy, code 1041C0700X
Behavioral Health & Social Service Providers Social Worker Clinical

All registered taxonomy codes

This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
1041C0700X Clinical Social Worker Clinical 73557 CA primary
1041C0700X Clinical Social Worker Clinical 11557310-3501 UT
1041C0700X Clinical Social Worker Clinical 09926365 CO

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.

NPI1134517600 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateJan 6, 2015
Last updatedOct 26, 2023
StatusActive
Sole proprietorYes
CredentialJ.D., LCSW
Practice address 518 HAMILTON AVE
Palo Alto, CA 94301
(650) 346-7698
This record was updated on Oct 26, 2023, which is recent enough that the contact details are likely still accurate.

Number check

1134517600 passes the NPI check digit test The final digit 0 matches the value computed from the first nine digits, so this is a well-formed NPI.
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 3 4 5 1 7 6 0
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 1 6 4 1 1 5 6 0

Sum = 50 · next multiple of 10 = 50 · 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.

Common questions

What is NPI number 1134517600?
NPI 1134517600 is the National Provider Identifier assigned to Mary Ellen Lemieux, J.D., LCSW in Palo Alto, CA. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Clinical cover?
A social worker who holds a master's or doctoral degree in social work from an accredited school of social work in addition to at least two years of post-master's supervised experience in a clinical setting. The social worker must be licensed, certified, or registered at the clinical level in the jurisdiction of…
How do I contact Mary Ellen Lemieux, J.D., LCSW?
The phone number on file with NPPES is (650) 346-7698, last updated Oct 26, 2023. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Mary Ellen Lemieux, J.D., LCSW accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1134517600 a valid number?
Yes. 1134517600 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.