Knockout Plumbing & Mech LLC
Licensed plumber in Seattle, Washington
Knockout Plumbing & Mech LLC holds Washington L&I licence KNOCKPM782DB, active, licensed since 25 Mar 2022, rated 4.9 from 49 Google reviews. Bonded for $6,000 with Western Surety Co. Washington L&I record: 0 open lawsuits against the bond, 1 infraction, citation or debarment, 0 resolved.
Read before hiring: 1 infraction, citation or debarment on the Washington L&I record. Details below, from the board's own record.
Report card
- Licence activeWashington L&I #KNOCKPM782DB, Residential. Issued 25 Mar 2022, expires 25 Mar 2028.
- Licensed 5 yrsSince 25 Mar 2022.
- Bonded$6,000 with Western Surety Co, since 25 Mar 2022. Washington sets the bond by licence type ($30,000 for a general contractor, $15,000 for a specialty contractor, $4,000 for an electrical contractor), so the amount shows the kind of licence, not the size or quality of the business.
- Liability insuredFederated Mutual Ins Co, $1,000,000, valid to 14 Jul 2027.
- Complaints on record0 open lawsuits against the bond, 1 infraction, citation or debarment, 0 resolved.Details on the Washington L&I record
- 9 building permits since 2020Naming this business as the contractor (City of Bellevue), most recently 6 Apr 2026.
Checked against the Washington State Department of Labor & Industries (L&I) register on 4 Nov 2026.
Google reviews
4.9(49 reviews)Mindy Martin★★★★★ a year agoView on Google
Excellent experience. I was considering replacing my water heater back in the spring and Knockout was one of the companies I shortlisted to talk to. Ultimately I decided to wait on replacement, but Knockout was definitely at the top of my list. When my water heater started leaking the other day, I immediately reached out to Knockout, and they were able to get me scheduled the next day! I was given the choice between …
Veronica Seifner★★★★★ 11 months agoView on Google
Knockout was great to work with - very courteous, responsive, and fair pricing. Zach came out to cap off a gas line for an appliance we switched to electric. The option was to do it from the inside or from the outside and remove the dedicated pipe altogether. Zach gave reasonable pricing (checked with two other companies) and was able to get the job done right away with expertise and professionalism. Knockout will be…
Margot Potts★★★★★ 5 months agoView on Google
Zack and his crew were able to come within a couple days of calling and resolved my issue within minutes. They were very friendly and generous - highly recommend!
Justin Gerardy★★★★★ 4 months agoView on Google
As a restaurant owner in Seattle, I tend to find it infuriating when tradespeople over charge. It’s a real problem in this city. Knockout was fair and fast. Can’t say how much I appreciate it. I’ll be back for sure.
Andrea Giraudo★★★★★ 2 years agoView on Google
I cannot recommend Knockout Plumbing and specifically Colin Forster enough! I was in a bind trying to sell my house from across the country and the buyers had some plumbing related requests before agreeing to move forward. Colin was super fast to get back to me, understand the asks, assess the actual work, and complete the fixes. He was so understanding and patient, walking me through what needed to be done and handl…
Read all 49 reviews on Google Reviews and photos from Google, 4 Nov 2026.
Recent permits
Building permits pulled under licence #KNOCKPM782DB, from City of Bellevue open data, which names contractors up to 3 Nov 2026. Locations are shown to ZIP code only.
- 6 Apr 2026 · Plumbing No Plan Review · ZIP 98008A Single Family Residential Repair or Replacement None Project Involving (3 Toilet, 4 Bathroom Sink, 1 Dishwasher, 1 Clothes Washer, 3 Shower, Tub, or...
- 7 Oct 2025 · Plumbing No Plan Review · ZIP 98008A Single Family Residential Repair or Replacement None Project Involving (1 Water Service - 1")
- 18 Oct 2024 · Plumbing No Plan Review · ZIP 98007A Single Family Residential Alteration to Existing Structure None Project Involving (1 Toilet, 1 Bathroom Sink, 1 Shower, Tub, or Combo)
- 19 Aug 2024 · Plumbing No Plan Review · ZIP 98005A Single Family Residential Repair or Replacement None Project Involving (1 Water Service - 1", 1 Pressure Reducing Valve)
- 3 Nov 2023 · Side Sewer Connection · ZIP 98006Tie in ADU sewer main into neighbors yard SDR35. Directionally bore new 1inch PEX water main from front of house to backyard garage. Travel; setup of drill;...
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Score 57.5 / 100. Claiming this listing or using Theo never changes it. How we rank
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