BackflowNear Test-Due Reminder

Approved backflow testers in Seattle, WA

50 backflow testing businesses work within 25 miles of Seattle, 9 of them based in town. Every one is on the approved tester list of 7 water utilities.

50 businesses within 25 miles

Backflow testing companies near Seattle

What the badges mean
✓ WA Utility-Approved Tester Verified On the city list
The company is on a water utility's own approved list (the second badge names the list). That is the utility's approval, not a state license, and it counts for that utility.
3 certified testers
How many certified testers the roster lists at this business.
★ 4.8 (25 reviews)
The Google rating, shown as Google reports it. It does not change the order.

Order is by our quality score, never by payment. How we verify listings.

Are you a backflow testing company near Seattle? One sponsor per county, clearly labelled. Sponsor this county

McKinstry

90/100
✓ WA Utility-Approved Tester Verified ★ 3.8 (67 reviews) On City of Bellevue list Backflow Testing

5005 3rd Ave S, Seattle, WA 98134 · under 1 mile from Seattle

Call (206) 762-3311 Details Website
Verified Oct 2026 · Unclaimed listing

The Safety Team, Inc.

90/100
✓ WA Utility-Approved Tester Verified ★ 4.1 (13 reviews) On City of Bellevue list Backflow Testing

670 S Lucile St, Seattle, WA 98108 · under 1 mile from Seattle

Call (206) 762-1450 Details Website
Verified Oct 2026 · Unclaimed listing

Iliad, Inc.

90/100
✓ WA Utility-Approved Tester Verified On City of Bellevue list Backflow Testing

1107 S Bailey St, Seattle, WA 98108 · under 1 mile from Seattle

Call (206) 282-4200 Details Website
Verified Oct 2026 · Unclaimed listing

SJS Mechanical

90/100
✓ WA Utility-Approved Tester Verified On City of Bellevue list Backflow Testing

309 S Cloverdale St, Seattle, WA 98108 · 2 mi from Seattle

Call (206) 763-0334 Details Website
Verified Oct 2026 · Unclaimed listing

Guardian Security

90/100
✓ WA Utility-Approved Tester Verified ★ 4.3 (274 reviews) On City of Bellevue listOn City of Snoqualmie list Backflow Testing

1743 1st Ave S, Seattle, WA 98134 · 2 mi from Seattle

Call (206) 622-6545 Details Website
Verified Oct 2026 · Unclaimed listing

Columbia Fire

90/100
✓ WA Utility-Approved Tester Verified ★ 4.9 (27 reviews) On City of Bellevue listOn City of Sumner list Backflow Testing

9520 10th Ave S #150, Seattle, WA 98108 · 3 mi from Seattle

Call (206) 232-8569 Details Website
Verified Oct 2026 · Unclaimed listing

Enviromech

90/100
✓ WA Utility-Approved Tester Verified ★ 5 (14 reviews) On City of Bellevue list Backflow Testing

430 SW 153rd St, Burien, WA 98166 · 6 mi from Seattle

Call (206) 762-1960 Details Website
Verified Oct 2026 · Unclaimed listing

All Phase Plumbing

90/100
✓ WA Utility-Approved Tester Verified ★ 4.8 (52 reviews) On City of Bellevue list Backflow Testing

14101 Interurban Ave S Unit 78-A, Tukwila, WA 98168 · 6 mi from Seattle

Call (206) 772-6077 Details Website
Verified Oct 2026 · Unclaimed listing

AAA Fire Protection

90/100
✓ WA Utility-Approved Tester Verified ★ 4.8 (637 reviews) On Washington Water list Backflow Testing

3013 3rd Ave N, Seattle, WA 98109 · 6 mi from Seattle

Call (800) 223-3473 Details Website
Verified Oct 2026 · Unclaimed listing

Holmberg Mechanical

90/100
✓ WA Utility-Approved Tester Verified ★ 4.2 (20 reviews) On City of Bellevue list Backflow Testing

12001 SE 9th Pl, Bellevue, WA 98005 · 8 mi from Seattle

Call (425) 822-2233 Details Website
Verified Oct 2026 · Unclaimed listing

MacDonald Miller

90/100
✓ WA Utility-Approved Tester Verified ★ 3 (4 reviews) On City of Bellevue list Backflow Testing

15395 SE 30th Pl Ste 120, Bellevue, WA 98007 · 9 mi from Seattle

Call (206) 767-7995 Details Website
Verified Oct 2026 · Unclaimed listing

Fire Chief Equipment

90/100
✓ WA Utility-Approved Tester Verified ★ 4.7 (9 reviews) On City of Bellevue list Backflow Testing

14214 NE 21st St, Bellevue, WA 98007 · 10 mi from Seattle

Call (425) 522-1269 Details Website
Verified Oct 2026 · Unclaimed listing

Archer Construction

90/100
✓ WA Utility-Approved Tester Verified ★ 4.1 (14 reviews) On City of Bellevue listOn City of Olympia list Backflow Testing

7855 S 206th St, Kent, WA 98032 · 11 mi from Seattle

Call (253) 872-7222 Details Website
Verified Oct 2026 · Unclaimed listing

Uyeta Landscape

90/100
✓ WA Utility-Approved Tester Verified ★ 4.4 (79 reviews) On City of Bellevue list Backflow Testing

19605 106th Ave SE, Renton, WA 98055 · 11 mi from Seattle

Call (253) 859-8589 Details Website
Verified Oct 2026 · Unclaimed listing

Alpine Sprinklers

90/100
✓ WA Utility-Approved Tester Verified ★ 3.8 (28 reviews) On City of Bellevue listOn Washington Water listOn City of Snoqualmie list Backflow Testing

1420 NW Gilman Blvd #2, Issaquah, WA 98027 · 13 mi from Seattle

Call (425) 391-8701 Details Website
Verified Oct 2026 · Unclaimed listing

Auburn Mechanical

90/100
✓ WA Utility-Approved Tester Verified ★ 3.6 (29 reviews) On City of Bellevue list Backflow Testing

2621 W Valley Hwy N, Auburn, WA 98001 · 16 mi from Seattle

Call (253) 838-9780 Details Website
Verified Oct 2026 · Unclaimed listing

Price reports

What a backflow test costs in Seattle

Not enough reports yet for Seattle to show a range. Be one of the first: it takes a minute and stays anonymous.

Published prices nationwide

$29.99 to $100 per assembly

Based on 14 published prices · Read Oct 2026 Prices testing businesses list on their own websites, from our cost guide. Listed prices, not what people paid.

Every published price, with its source: what a backflow test costs.

Failed test? Published repair, rebuild and replacement prices: what a backflow repair or replacement costs.

Had your backflow test done? Share what you paid to see local prices.

Metro guide: Backflow testing in Seattle: every utility's rules, filing portals and published prices in one place.

Seattle Public Utilities: backflow test rules

  • Who must test. All installed backflow assemblies must be tested every year by a State of Washington certified backflow assembly tester, and after any repair or replacement; a copy of the report goes directly to SPU. Source.
  • How the report is filed. After the test, the certified tester submits the test report directly to Seattle Public Utilities. Source.
  • Tester registration. Testing must be done by a State of Washington certified Backflow Assembly Tester, and the tester must give SPU copies of the current state certification and test kit calibration certificates; reports cannot be submitted without them. Source.
  • Approved testers. SPU does not publish its own tester list; it points customers to the Washington Certification Services listing of state certified testers. Source.
  • If a test is missed. If testing is not completed, SPU may assess non-compliance charges and may terminate water service. Source.

Everything about Seattle Public Utilities's backflow program

Never miss your annual backflow test

Most water utilities require the backflow assembly on an irrigation, fire or commercial line to be tested every year, and a missed test can mean a shutoff notice. Tell us when yours was last tested in Seattle and we'll text you a month before it is due, with certified local testers ready to book.

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Backflow testing questions in Seattle

Where are the backflow testing businesses listed for Seattle based?

50 backflow testing businesses are listed within 25 miles of Seattle. 9 are based in Seattle itself, 17 more within 15 miles and 24 further out, up to 24 miles away. Other towns with more than one listing: Bellevue (4), Renton (4) and Auburn (3). The closest is McKinstry, under 1 mile from Seattle.

Which tester lists are the businesses near Seattle on?

Every one is on the approved tester list of 7 water utilities.

Which water utility sets the backflow test rules in Seattle?

Seattle Public Utilities. Who must test: All installed backflow assemblies must be tested every year by a State of Washington certified backflow assembly tester, and after any repair or replacement; a copy of the report goes directly to SPU.

How many of the backflow testing businesses near Seattle have Google reviews?

44 of the 50 listed for Seattle have 3 or more Google reviews. Day & Nite Plumbing & Heating has the most reviews, 1,847, with an average of 4.8 stars, as Google showed them at our last check.

Approved list: City of Bellevue backflow testing companies, City of Bellevue Utilities.

Approved list: Washington Water companies with certified backflow testers, Washington Water Service.

Approved list: City of Spokane backflow assembly testers, City of Spokane Water Department.

Approved list: City of Olympia certified backflow testers, City of Olympia Drinking Water Utility.

Approved list: Clark Public Utilities list of Washington State certified backflow testers, Clark Public Utilities.

Approved list: City of Lacey certified backflow assembly testers (BAT) list, City of Lacey Public Works.

Approved list: City of Yakima certified backflow prevention assembly testers, City of Yakima Water/Irrigation Division.

Approved list: City of Ridgefield approved backflow assembly testers, City of Ridgefield Public Works.

Approved list: City of Sumner approved backflow assembly testers, City of Sumner.

Approved list: City of DuPont certified backflow prevention assembly testers, City of DuPont Public Works.

Approved list: City of Snoqualmie backflow assembly testers, City of Snoqualmie.

Related site: Testing a fire line? The sprinkler system behind it needs its own inspections by a state-licensed fire protection company. Licensed fire sprinkler inspectors near Seattle on FireInspectorNear, our sister directory.

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