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Built to Serve Washington

Certified Backflow Testing provides certified backflow assembly testing, repair, installation, and premise isolation services throughout King, Snohomish, and Pierce Counties, with extended coverage into Thurston and surrounding areas.

We also test in Spokane County, Washington as well as Kootenai County, Idaho. Certified Backflow Testing regularly handles residential, commercial, municipal, and large-scale institutional properties across the state.

Don’t See Your City? Call Us Anyway.

We regularly accommodate properties outside our standard routes, especially commercial, municipal, and premise isolation repairs & installations.

Outside of WA or Northern ID? Find providers in other markets here.

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Algona

98001

Backflow testing in Algona is completed annually based on your last test date.

Arlington

98223

Backflow testing in Arlington typically follows an annual compliance cycle with notices issued in spring.

Auburn

98001, 98002, 98092

Backflow testing in Auburn is performed year-round to meet annual water purveyor requirements.

Bellevue

98004, 98005, 98006, 98007, 98008

Backflow testing in Bellevue happens all year long, with most notice letters sent to water customers in April.

Black Diamond

98010

Backflow testing in Black Diamond is scheduled throughout the year to ensure ongoing compliance.

Bothell

98011, 98012, 98021

Backflow testing in Bothell is completed annually based on your last test date.

Burien

98166, 98168

Backflow testing in Burien is performed year-round to meet annual water purveyor requirements.

Carnation

98014

Backflow testing in Carnation typically follows an annual compliance cycle with notices issued in spring.

Coeur d'Alene, ID

83814, 83815

Backflow testing in Coeur d'Alene, ID follows a 12-month compliance cycle.

Covington

98042

Backflow testing in Covington is scheduled throughout the year to ensure ongoing compliance.

Duvall

98019

Backflow testing in Duvall is completed annually based on your last test date.

Edmonds

98020, 98026

Backflow testing in Edmonds is performed year-round to meet annual water purveyor requirements.

Everett

98201, 98203, 98204, 98208

Backflow testing in Everett typically follows an annual compliance cycle with notices issued in spring.

Fall City

98024

Backflow testing in Fall City is scheduled throughout the year to ensure ongoing compliance.

Federal Way

98003, 98023

Backflow testing in Federal Way is completed annually based on your last test date.

Issaquah

98027, 98029, 98075

Backflow testing in Issaquah is performed year-round, with most reports due in May and June.

Kent

98030, 98031, 98032, 98042

Backflow testing in Kent typically follows an annual compliance cycle with notices issued in spring.

Kirkland

98033, 98034

Backflow testing in Kirkland is completed year-round, based on an annual cycle from your last test date.

Lacey

98503, 98516

Backflow testing in Lacey is completed annually based on your last test date.

Lake Stevens

98258

Backflow testing in Lake Stevens is performed year-round to meet annual water purveyor requirements.

Lakewood

98498, 98499

Backflow testing in Lakewood is performed year-round to meet annual water purveyor requirements.

Liberty Lake

99016, 99019

Backflow testing in Liberty Lake is scheduled throughout the year to ensure ongoing compliance.

Lynnwood

98036, 98037

Backflow testing in Lynnwood typically follows an annual compliance cycle with notices issued in spring.

Marysville

98270, 98271

Backflow testing in Marysville is scheduled throughout the year to ensure ongoing compliance.

Mercer Island

98040

Backflow testing in Mercer Island is generally due in June.

Mill Creek

98012

Backflow testing in Mill Creek is performed year-round to meet annual water purveyor requirements.

Monroe

98272

Backflow testing in Monroe typically follows an annual compliance cycle with notices issued in spring.

Mountlake Terrace

98043

Backflow testing in Mountlake Terrace is scheduled throughout the year to ensure ongoing compliance.

Mount Vernon

98273, 98274

Backflow testing in Mount Vernon is scheduled throughout the year to ensure ongoing compliance.

Mukilteo

98275

Backflow testing in Mukilteo is completed annually based on your last test date.

Newcastle

98056, 98059

Backflow testing in Newcastle is typically scheduled in March each year.

North Bend

98045

Backflow testing in North Bend typically follows an annual compliance cycle with notices issued in spring.

Olympia

98501, 98502, 98512

Backflow testing in Olympia is scheduled throughout the year to ensure ongoing compliance.

Orting

98360

Backflow testing in Orting, WA is done in the first 3 quarters of the year.

Pacific

98047

Backflow testing in Pacific is completed annually based on your last test date.

Post Falls, ID

83854, 83877

Backflow testing in Post Falls, ID is performed in the first half of the year to meet annual water purveyor requirements.

Puyallup

98371, 98372, 98373

Backflow testing in Puyallup is performed year-round to meet annual water purveyor requirements.

Redmond

98052, 98053

Backflow testing in Redmond is performed throughout the year, with certain areas due in June.

Renton

98055, 98056, 98057, 98058, 98059

Backflow testing in Renton is completed year-round, though some water purveyors require testing in June.

Sammamish

98074, 98075

Backflow testing in Sammamish occurs year-round, with peak report deadlines in May and June.

Seattle

98101, 98103, 98105, 98115, 98125

Backflow testing in Seattle follows a rolling 12-month cycle based on your last completed test.

Stanwood

98292

Backflow testing in Stanwood is scheduled throughout the year to ensure ongoing compliance.

Snohomish

98290, 98296

Backflow testing in Snohomish typically follows an annual compliance cycle with notices issued in spring.

Spokane

99201, 99205, 99210, 99217, 99202, 99207, 99211, 99218, 99203, 99208, 99212, 99219, 99204, 99209, 99213, 99220

Backflow testing in Spokane is scheduled throughout the year to ensure ongoing compliance.

Sumner

98390

Backflow testing in Sumner is scheduled throughout the year to ensure ongoing compliance.

Tacoma

98402, 98405, 98409

Backflow testing in Tacoma, WA is completed annually based on your last test date.

Tukwila

98188

Backflow testing in Tukwila is performed year-round to meet annual water purveyor requirements.

Woodinville

98072

Backflow testing in Woodinville is due annually by the end of August.

Yarrow Point

98004

Backflow testing in Yarrow Point is scheduled throughout the year to ensure ongoing compliance.

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