Organization provider

MERCER ISLAND THERAPY, PLLC

Clinical Psychologist Speech-Language Pathologist Clinical Social Worker

MERCER ISLAND THERAPY, PLLC is an organization registered with the National Plan and Provider Enumeration System (NPPES) under NPI 1003129461, based in Mercer Island, WA. The organization lists 3 taxonomy classifications, with Clinical Social Worker recorded as primary.

Getting there

Here is what surrounds this office in Mercer Island, based on OpenStreetMap data collected Sep 7, 2026. Parking is available about 0.28 mi away at Mercer Island Park & Ride. There is EV charging 0.24 mi from the office — useful if you are driving in from out of town. The nearest transit stop is 997 ft away, served by 78th Ave SE & SE 32nd St. A pharmacy sits 0.21 mi from the entrance (Rite Aid), which helps if you leave with a prescription. If you arrive early, there is a coffee shop 677 ft away.

8015 SE 28TH ST STE 309, Mercer Island, WA 98040 Open in Google Maps →

Getting here and what is nearby

Parking 463 ft ~2 min
Grocery QFC 476 ft ~2 min

7823 Southeast 28th Street, Mercer Island 98040

24/7

+1-206-230-0745

Website

Directions in Google Maps →

Coffee Hub Boba 579 ft ~3 min

2900 78th Avenue Southeast, Mercer Island 98040

Directions in Google Maps →

Parking 573 ft ~3 min
Restaurant Einstein Bros. Bagels 577 ft ~3 min

7808 Southeast 28th Street, Mercer Island 98040

Mo-Fr 06:00-15:00; Sa,Su 07:00-15:00

Website

Directions in Google Maps →

Transit 78th Ave SE & SE 28th St 651 ft ~3 min
Coffee Homegrown 625 ft ~3 min

3016 78th Avenue Southeast, Mercer Island 98040

Mo-Su 07:00-20:00

Website

Directions in Google Maps →

Coffee L’Experience Paris 677 ft ~3 min

3020 78th Avenue Southeast, Mercer Island 98040

Website

Directions in Google Maps →

Transit 78th Ave SE & SE 28th St 745 ft ~3 min
Convenience Jacksons 795 ft ~4 min

2903 78th Avenue Southeast, Mercer Island 98040

Directions in Google Maps →

Restaurant McDonald's 895 ft ~4 min

2807 78th Avenue Southeast, Mercer Island 98040-2818

Mo-Th 05:00-23:00; Fr,Sa 06:00-23:00; Su 06:00-23:00

+1-206-232-9175

Website

Directions in Google Maps →

Restaurant Sushi Joa 916 ft ~4 min

2717 78th Avenue Southeast, Mercer Island 98040

Mo-Th 11:30-21:00; Fr 11:30-21:30; Sa 11:30-21:00

Website

Directions in Google Maps →

Transit 78th Ave SE & SE 32nd St 997 ft ~4 min
Pharmacy Walgreens 988 ft ~4 min

Mo-Su 07:00-24:00

Directions in Google Maps →

Pharmacy Rite Aid 0.21 mi ~5 min

3023 78th Avenue Southeast

Mo-Su 07:00-22:00

Website

Directions in Google Maps →

Grocery Metropolitan Market 0.23 mi ~5 min

2755 77th Avenue Southeast, Mercer Island 98040

Mo-Su 06:00-23:00

+1-206-232-2577

Directions in Google Maps →

EV charging 0.24 mi ~5 min
Parking Mercer Island Park & Ride 0.28 mi ~6 min

8000 North Mercer Way, Mercer Island 98040

Directions in Google Maps →

Convenience ExtraMile 0.29 mi ~6 min

7655 Sunset Highway, Mercer Island 98040

Directions in Google Maps →

OpenStreetMap via Overpass · ODbL 800 m radius Updated Sep 7, 2026

Distances are straight‑line estimates — walking routes may be longer. Hours and phone numbers can change; call ahead to confirm.

Credentials and Medicare

State licence
LicenceStateSpecialty
LL00001598 WA Speech-Language Pathologist

This provider holds licence LL00001598 issued in WA. A licence number in NPPES reflects what was filed at registration — it does not confirm the licence is still active today.

Medicare (PECOS)

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 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
103TC0700X Clinical Psychologist Clinical
235Z00000X Speech-Language Pathologist LL00001598 WA
1041C0700X Clinical Social Worker Clinical primary

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.

NPI1003129461 valid check digit
Entity typeOrganization (NPI-2)
Enumeration dateJul 14, 2010
Last updatedJan 3, 2022
StatusActive
Practice address 8015 SE 28TH ST STE 309
Mercer Island, WA 98040
(206) 236-1294
Fax (206) 257-3196
Mailing address 8015 SE 28TH ST SUITE 309
Mercer Island, WA 98040
Other names Northwest Speech Therapy / Spotlight Social Skills Former Legal Name
The last update on file is Jan 3, 2022. Providers are only required to update NPPES when their information changes, so an older date does not necessarily mean the details are wrong — but it is worth a quick call before you travel.

Number check

1003129461 passes the NPI check digit test The final digit 1 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 0 0 3 1 2 9 4 6
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 0 0 3 2 2 9 4 3

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.

Common questions

What is NPI number 1003129461?
NPI 1003129461 is the National Provider Identifier assigned to MERCER ISLAND THERAPY, PLLC in Mercer Island, WA. 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 MERCER ISLAND THERAPY, PLLC?
The phone number on file with NPPES is (206) 236-1294, last updated Jan 3, 2022. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Where do I park when visiting MERCER ISLAND THERAPY, PLLC?
Parking is about 0.28 mi from the office (Mercer Island Park & Ride). The closest transit stop is 997 ft away, on 78th Ave SE & SE 32nd St. Distances are straight-line estimates from OpenStreetMap, so walking routes may be slightly longer.
Is NPI 1003129461 a valid number?
Yes. 1003129461 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.