ContractorHistory

Washington contractor

MAINSTREAM PLUMBING LLC

First registered in Washington on May 28, 2019

License number
MAINSPL814K8
UBI
604451150
Trade
General contractor(all general contractor contractors in Washington)
L&I license type and specialty
CONSTRUCTION CONTRACTOR · GENERAL
City
ARLINGTON, WA(all contractors in Arlington)
Phone
(425) 239-1402

Current verification

  • Found: No Attorney General complaint records found
  • Review: Registration is not currently active
  • Review: Registration appears to be expired
  • Review: 6 other license records under the same UBI

From the state records below; each section shows its source and when it was last synced.

Registration

Status
OUT OF BUSINESS
Effective date
May 28, 2019
Expiration date
November 23, 2023

Source: L&I Contractor License Data - General, Washington State Department of Labor & Industries. Last synced October 7, 2026.

Related licenses

6 other license numbers are registered under the same UBI, 604451150. A UBI identifies one business with the state; a business may hold more than one license, renew under a new number, or register a new license after an earlier one closed.

  • DAPPER PLUMBINGACTIVE

    License DAPPEP*770C2 · PLUMBING CONTRACTOR · March 13, 2023 to August 22, 2027

  • DAPPER ELECTRICACTIVE

    License DAPPEE*793PN · ELECTRICAL CONTRACTOR · October 4, 2021 to October 4, 2027

  • DAPPER PLUMBINGEXPIRED

    License DAPPEP*764MQ · PLUMBING CONTRACTOR · July 18, 2024 to July 18, 2026 · suspension date May 21, 2025

  • MAINSTREAM PLUMBING LLCINACTIVE

    License MAINSPL798O7 · ELECTRICAL CONTRACTOR · October 4, 2021 to October 4, 2023

  • DAPPER HEATING & AIREXPIRED

    License DAPPEHA808RQ · CONSTRUCTION CONTRACTOR · January 12, 2021 to January 12, 2025

  • DAPPER PLUMBINGOUT OF BUSINESS

    License DAPPEP*807LC · CONSTRUCTION CONTRACTOR · June 3, 2020 to June 3, 2022 · suspension date May 21, 2022

Source: L&I Contractor License Data - General, Washington State Department of Labor & Industries. Last synced October 7, 2026.

Bond

L&I does not publish bond records for contractors with OUT OF BUSINESS status.

Source: L&I Contractor License Data - Bond, Washington State Department of Labor & Industries. Last synced October 9, 2026.

Liability insurance

L&I does not publish liability insurance records for contractors with OUT OF BUSINESS status.

Source: L&I Contractor License Data - Insurance, Washington State Department of Labor & Industries. Last synced October 9, 2026.

People

Principals L&I lists for this license.

L&I does not publish principal records for contractors with OUT OF BUSINESS status.

Source: L&I Contractor License - Principal Data, Washington State Department of Labor & Industries. Last synced October 9, 2026.

Attorney General complaints

No Attorney General complaint records found.

Matched on business name and city: MAINSTREAM PLUMBING in ARLINGTON. Complaints filed under another name or city are not included.

One other registered contractor shares this business name and city: MAINSTREAM PLUMBING LLC (MAINSPL798O7, INACTIVE). Complaints are matched by business name and city, so any complaint records shown here also appear on those pages. The records do not say which of these contractors a complaint was about.

A complaint record does not establish that the business violated the law.

Source: Attorney General Consumer Complaints, Washington State Attorney General's Office. Last synced October 9, 2026.

Record history

Changes to this contractor's state records since we began tracking them. The state's current-status tools do not show these.

No changes recorded since our records began on October 6, 2026.

Sources

Record last synced October 7, 2026.

Check this record against the state directly on L&I's Verify a Contractor page (search by license number MAINSPL814K8).