Willow ABA Services

Primary specialty

Behavior AnalystTaxonomy code 103K00000X

Legal business name

WILLOW ABA SERVICES

Practice address

8000 S Lincoln St Ste 10
Littleton, CO 80122-2725

Phone

(720) 316-7614

Fax

(720) 316-7614

NPI assigned

Jan 24, 2020

Last updated

Sep 26, 2025By the provider in NPPES

Organization subpart

No

Registry information is reported by the provider to CMS and is not verified. About this source

Authorized official

Name

Tanner Sierks Sierks

Title

Owner

Phone

(720) 319-7614

Specialties & licenses 1

Addresses

Electronic endpoints 2

Locations

Practitioners 2

Individual providers connected to this organization through Medicare benefit reassignment, Care Compare group membership or National Provider Directory roles, and the practitioner matching its NPPES authorized official.

• Alyson Martin, BCBA

  • Behavior Analyst
  • Bend, OR
  • NPI 1609605567
  NPD (past)
• Elana Shyman, BCBA

  • Behavior Analyst
  • Chicago, IL
  • NPI 1912744814
  NPD (past)

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1579824000000",
    "enumeration_type": "NPI-2",
    "last_updated_epoch": "1758844800000",
    "number": "1205466612",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "8000 S LINCOLN ST STE 10",
            "city": "LITTLETON",
            "state": "CO",
            "postal_code": "801222725",
            "telephone_number": "720-319-7614",
            "fax_number": "720-319-7614"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "8000 S LINCOLN ST STE 10",
            "city": "LITTLETON",
            "state": "CO",
            "postal_code": "801222725",
            "telephone_number": "720-316-7614",
            "fax_number": "720-316-7614"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "organization_name": "WILLOW ABA SERVICES",
        "organizational_subpart": "NO",
        "enumeration_date": "2020-01-24",
        "last_updated": "2025-09-26",
        "certification_date": "2025-09-26",
        "status": "A",
        "authorized_official_last_name": "SIERKS",
        "authorized_official_first_name": "TANNER SIERKS",
        "authorized_official_title_or_position": "OWNER",
        "authorized_official_telephone_number": "720-319-7614"
    },
    "taxonomies": [
        {
            "code": "103K00000X",
            "taxonomy_group": "",
            "desc": "Behavior Analyst",
            "state": "NU",
            "license": null,
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [
        {
            "endpointType": "CONNECT",
            "endpointTypeDescription": "CONNECT URL",
            "endpoint": "info@willowaba.com",
            "affiliation": "N",
            "endpointDescription": "HIPAA Compliant Email",
            "use": "DIRECT",
            "useDescription": "Direct",
            "contentType": "OTHER",
            "contentTypeDescription": "Other",
            "contentOtherDescription": "6143542249",
            "address_1": "12650 E Briarwood Ave",
            "city": "Centennial",
            "state": "CO",
            "country_code": "US",
            "postal_code": "801126792",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "endpointType": "CONNECT",
            "endpointTypeDescription": "CONNECT URL",
            "endpoint": "info@willowaba.com",
            "affiliation": "N",
            "endpointDescription": "HIPAA CompliantEmail",
            "use": "HIE",
            "useDescription": "Health Information Exchange (HIE)",
            "contentType": "OTHER",
            "contentTypeDescription": "Other",
            "contentOtherDescription": "Email",
            "address_1": "8000 S Lincoln St Ste 10",
            "city": "Littleton",
            "state": "CO",
            "country_code": "US",
            "postal_code": "801222725",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "other_names": []
}

• Ashley Williamson, MA, LPC
• Katherine S Williamson
• Dixie Darlene Willis, LPC, NCC
• Whitney Willits, APN, PMHNP-BC
• Philip M Willner, D.C.
• Willow ABA Services LLC - Golden (Willow ABA Services)
• Adam Christopher Wilson, PHD, LPC
• Bethany Wilson, LPC, BCN
• Chad Wilson
• Don Keith Wilson, CMT

• Behavior Analyst in Littleton, CO
• Providers in Littleton, CO by specialty
• Behavior Analyst in Colorado

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Sep 26, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.