Calvin Horace Knapp III, MD

Primary specialty

Dermatology PhysicianTaxonomy code 207N00000X

License

MD61463521 Issued in WA

Practice address

4004 Colby Ave
Everett, WA 98201-6203

Phone

(425) 339-5417

Fax

(425) 339-5429

NPI assigned

Mar 29, 2018

Sex

Male

Sole proprietor

No

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

Specialties & licenses 1

Addresses

Medicare fee-for-service enrollment

Enrolled in WA

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 1

Specialty

Dermatology

Education

Other, 2018

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

Optum Care Washington PLLCGroup PAC ID 6406752153, 684 clinicians

Practice addresses (Care Compare)

Procedures performed for Medicare patients

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

Practice roles

Locations

Interoperability endpoints

• FHIR API: https://api.platform.athenahealth.com/3889/brand/1/csg/1/fhir/r4
• Direct secure messaging: cknapp81611@direct.tecmc.com

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Optum Care Washington PLLC

  • Multi-Specialty Clinic/Center
  • Everett, WA
  • NPI 1831186766
  Medicare reassignment Care Compare group NPD
• The Polyclinic PLLC

  • Audiologist
  • Seattle, WA
  • NPI 1174594634

  Dermatology

  Medicare reassignment NPD
• Optum Care Washington PLLC

  • Durable Medical Equipment & Medical Supplies
  • Marysville, WA
  • NPI 1194428425
  NPD
• Optum Care Washington PLLC

  • Ambulatory Surgical Clinic/Center
  • Arlington, WA
  • NPI 1366154304
  NPD
• The Polyclinic

  • Ambulatory Surgical Clinic/Center
  • Seattle, WA
  • NPI 1073944039
  NPD
• The Polyclinic PLLC

  • Durable Medical Equipment & Medical Supplies
  • Tacoma, WA
  • NPI 1831411487
  NPD
• Optum Care Washington PLLC

  • Ambulatory Surgical Clinic/Center
  • Everett, WA
  • NPI 1154318103
  NPD (past)

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

{
    "created_epoch": "1522281600000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1776384000000",
    "number": "1225533458",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "7600 EVERGREEN WAY",
            "city": "EVERETT",
            "state": "WA",
            "postal_code": "982036421",
            "telephone_number": "206-860-5414"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "4004 COLBY AVE",
            "city": "EVERETT",
            "state": "WA",
            "postal_code": "982016203",
            "telephone_number": "425-339-5417",
            "fax_number": "425-339-5429"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "KNAPP",
        "first_name": "CALVIN",
        "middle_name": "HORACE",
        "name_suffix": "III",
        "credential": "MD",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2018-03-29",
        "last_updated": "2026-04-17",
        "certification_date": "2026-04-17",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207N00000X",
            "taxonomy_group": "",
            "desc": "Dermatology",
            "state": "WA",
            "license": "MD61463521",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Valerie Jean Kline, OTR
• Cecilia Klinger
• Sonya Ruthlaveda Klippert
• Stefka Louise Kmiecik
• Roger Knaphus, DDS
• George Byron Knapp, PSY.D.
• Laura Knapp, MSW
• Victoria Taylor Knapp, CMA
• Deborah Knaus, BAS
• Knead to Heal, LLC

• Dermatology Physician in Everett, WA
• Providers in Everett, WA by specialty
• Dermatology Physician in Washington

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Apr 17, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• Medicare Care Compare (CMS): clinician profile, group practices, facility affiliations, MIPS scores and star ratings.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.