Seattle & King County, WA Certified Backflow Testing & Grease Trap (FOG) Directory (2026 Rules & Prices)

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Seattle & King County Consumer & Compliance Alert (Verified 2026-10-27)

SPU $105-PER-ASSEMBLY REMINDER CHARGE & SHUTOFF RISK: Seattle Public Utilities charges $105 per backflow preventer for each reminder letter once 30 days pass without a passing test on file, plus $155 for a late-test shutoff notice, and may terminate water service. SPU charges $0 for SAMS portal submissions — independent DOH-certified BATs in Seattle advertise residential tests from about $55–$80 with no reporting fee.

POTABLE WATER & IRRIGATION / FIRE

Seattle Public Utilities (SPU) — Cross-Connection Control & Backflow Prevention Program Rules

Official Program	Backflow Prevention & Cross-Connection Control Program (SPU Policy CS-105 & WAC 246-290-490) ↗
Filing Portal & Fee	SPU SAMS Cross-Connection Tester Portal (NJBSoft) $0 (SPU states it does not charge to submit backflow test reports through the SAMS portal)
Tester Registry	View Official Municipal Tester List ↗
Annual Deadline Rule	Every installed backflow assembly must be tested annually by a Washington State DOH-certified Backflow Assembly Tester (BAT), and again after any repair or replacement; new assemblies must be tested before being put into service. SPU mails test-due notices, and proof of a passing test is expected within 30 days of the original notice. The tester submits the report directly to SPU — since August 17, 2026, all test reports must be entered electronically in SPU's SAMS Tester Portal (the SPU_TestReports email inbox is no longer accepted), using the Letter Code from the customer's notice or the exact assembly serial number on file.
Non-Compliance Penalty	$105 per backflow preventer for each reminder letter when proof of a passing test is not received within 30 days of the original notice, a $155 late assembly test shutoff notice charge, and possible termination of water service.
Utility Contact	(206) 684-3536 (SPU Cross-Connection Control & Backflow Prevention Program, SPU_Backflow@seattle.gov) • Seattle Municipal Tower, 700 5th Avenue, Suite 4900, Seattle, WA 98104 (Mailing: PO Box 34018, Seattle, WA 98124-5177)

RESTAURANT & COMMERCIAL KITCHEN FOG

Seattle Public Utilities (SPU) Fats, Oils & Grease (FOG) Program & King County Industrial Waste (KCIW) Rules

Official Program	SPU Commercial Kitchen FOG Requirements (SMC 21.16.300–21.16.310) & King County Industrial Waste Local Discharge Limits ↗
Mandatory Pumping Schedule	Any Seattle business with commercial kitchen plumbing fixtures and a King County Food Business Permit must install and maintain a grease interceptor (SMC 21.16.310 A) — including delis, coffee and ice cream shops, pizzerias, and caterers. Interceptors must be cleaned per the manufacturer's specifications and whenever they are more than 25% full of grease and food waste (SMC 21.16.310 B); SPU guidance says every facility must have its interceptor professionally cleaned at least once per year, and gravity interceptors may only be cleaned by a professional. Emulsifiers, enzymes, and bio-additives are prohibited (SMC 21.16.310 D), and discharges above 100 ppm FOG are prohibited (SMC 21.16.300).
Manifest & Hauler Rule	SPU provides a FOG Pretreatment Device Maintenance Log for food service establishments to record every interceptor cleaning (date, who cleaned it, and what was removed); keep the log and hauler service receipts on site for SPU and King County inspectors. King County may require some polar-FOG dischargers to prepare a written FOG Control Plan.
Violation Fines	Seattle Municipal Code penalties for FOG non-compliance range from $250 to $5,000, plus recovery of any City costs from grease-related damage to the sanitary sewer; King County Industrial Waste enforces its 100 mg/L nonpolar FOG limit and free-floating polar FOG rules.
Environmental Desk	(206) 684-3000 / greenbusiness@seattle.gov (Seattle Public Utilities); (206) 477-5371 (King County Wastewater Treatment Division Industrial Waste Section)
Governing Code	SPU Cross-Connection Control Policy CS-105, WAC 246-290-490 (cross-connection control) & WAC 246-292-036 (test report contents); SPU Customer Charges FIN-220.1

Verified Certified Testers & Permitted FOG Haulers in Seattle & King County

Filter by residential availability, 24/7 emergency response, or direct electronic utility portal filing.

Showing all 5 verified providers

★ Verified Residential-Friendly & Instant Portal Filing Pro

Pop's Backflow Testing

Backflow Testing✓ Takes Residential Jobs✓ Direct Portal Filing (SPU SAMS Cross-Connection Tester Portal)

Certified backflow tester serving Seattle and the south King County corridor for both residential and commercial assemblies, filing reports with the water provider, emailing customers a copy the same day, and offering a free annual test reminder service.

Credentials: WA DOH-Certified Backflow Assembly Tester (Cert. #B5596) • L&I-Certified Backflow Plumber; City of Seattle Business License #777789 Area / Address: Serving Seattle, West Seattle, Burien, Des Moines, SeaTac & Tukwila (Mailing: 10624 Irene Ave SW, Lakewood, WA 98499) Source: Official website (backflowtestingseattle.com, Rates page) & WCS Hire-a-BAT program ↗

Published rates $65–$80 (ball-valve assemblies 2" and under); test reports sent to the water provider and emailed to you same day

Call (206) 551-5174

Certified Backflow Testing, Inc.

Backflow Testing✓ Takes Residential Jobs✓ Direct Portal Filing (SPU SAMS Cross-Connection Tester Portal)

23+ year Puget Sound backflow specialist completing 15,000+ tests a year for homes, HOAs, businesses, and municipalities across King, Snohomish, and Pierce Counties, submitting reports directly to the water provider.

Credentials: Washington State Certified Backflow Assembly Testers • Residential, Commercial, HOA, Municipal & Hydrant Assembly Testing and Repair Area / Address: 1410 235th Pl SE, Sammamish, WA 98075 (Serving King, Snohomish & Pierce Counties) Source: Official website (certified-backflowtesting.com) & Washington Secretary of State corporate record (1410 235th Pl SE, Sammamish) ↗

Residential exterior tests from $55, interior assemblies from $65, assemblies over 2" $100; direct report submission to your water provider

Call (425) 427-8889

Best Plumbing Group

Backflow TestingGrease Trap / FOG Hauling✓ Takes Residential Jobs⚡ 24/7 Emergency

Seattle plumbing contractor since 1968 at 8820 Aurora Ave N offering backflow testing, inspection, installation, and repair for homes and businesses, plus commercial grease interceptor installation and side sewer services listed by SPU.

Credentials: WA Licensed Plumbing Contractor #BESTPGL973CD • SPU FOG Service Provider List — Large & Small Grease Interceptor Installation, Side Sewer Cleaning & Rehab Area / Address: 8820 Aurora Ave N, Seattle, WA 98103 Source: Official website (bestplumbing.com) & SPU FOG Service Provider List (updated 8/4/2024) ↗

Free job estimates; backflow installation, testing, inspection & repair; 24/7 service available

Call (206) 633-1700

★ Verified Residential-Friendly & Instant Portal Filing Pro

A Advanced Septic Services, Inc.

Grease Trap / FOG Hauling⚡ 24/7 Emergency

Auburn pumping company listed by Seattle Public Utilities for installing and maintaining both large and small grease interceptors, and a King County certified liquid waste hauler with a 24-hour service line.

Credentials: King County Certified Liquid Waste Pumper/Hauler (Reg. KC777) • SPU FOG Service Provider List — Large & Small Grease Interceptor Installation & Maintenance Area / Address: 1602 W Valley Hwy S, Auburn, WA 98001 Source: SPU FOG Service Provider List (updated 8/4/2024), King County Certified Liquid Waste Pumper/Hauler list & aadvancedservices.com ↗

24-hour service line (253) 435-9999; office (253) 201-2360 Mon–Fri 7 a.m.–6 p.m.

Call (253) 435-9999

Mahoney Environmental (Restaurant Cooking Oil Recycling & Grease Trap Services)

Grease Trap / FOG Hauling

Restaurant services provider with a Seattle (98108) operation listed by SPU for grease interceptor maintenance, offering commercial grease trap cleaning and installation plus used cooking oil collection and recycling, with Spanish-speaking support.

Credentials: SPU FOG Service Provider List — Grease Interceptor Maintenance • Used Cooking Oil Collection & Recycling Area / Address: Seattle, WA 98108 (per SPU FOG Service Provider List) Source: SPU FOG Service Provider List (updated 8/4/2024) & Official website (mahoneyes.com) ↗

Commercial grease trap cleaning & installation plus scheduled used cooking oil collection; call or text (971) 254-2033

Call (800) 892-9392

LOCAL FAIR-PRICE BENCHMARK CALCULATOR

Seattle & King County, WA Backflow & Grease Trap Cost Estimator

Check what your job should actually cost in Seattle & King County before accepting an inflated quote—and compare against municipal non-compliance penalties.

Select Compliance Job Type

Number of Assemblies / Traps

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Seattle & King County Fair-Price Benchmark

$55 – $80

Includes electronic submission to SPU SAMS Cross-Connection Tester Portal (NJBSoft).

Overpriced Quote Alert: Commercial fire/plumbing firms in Seattle & King County frequently quote $150+ for single-valve visits. City non-compliance penalty/shutoff exposure starts at $105+.

Seattle & King County, WA Backflow & Grease Trap FAQs

Direct answers sourced from Seattle Public Utilities (SPU) — Cross-Connection Control & Backflow Prevention Program and Seattle Public Utilities (SPU) Fats, Oils & Grease (FOG) Program & King County Industrial Waste (KCIW) regulations.

Who has to test backflow assemblies in Seattle, and what happens if I miss the deadline?

Seattle Public Utilities (SPU) requires every installed backflow assembly to be tested annually by a Washington State DOH-certified Backflow Assembly Tester (BAT), and after any repair or replacement. If proof of a passing test isn't received within 30 days of SPU's original notice, SPU's Customer Charges (FIN-220.1) add $105 per backflow preventer for each reminder letter and $155 for a late assembly test shutoff notice, and SPU may terminate water service. Questions go to SPU_Backflow@seattle.gov or (206) 684-3536.

How are backflow test reports submitted to Seattle Public Utilities in 2026?

Since August 17, 2026, SPU only accepts test reports entered electronically in its SAMS Cross-Connection Tester Portal (NJBSoft); the old SPU_TestReports email inbox is closed. Your tester submits the report directly to SPU using the Letter Code from your notice or the exact assembly serial number, and must have a current BAT certification and test kit calibration on file. SPU charges nothing to submit reports, so you should not pay a separate 'filing fee.'

What are the grease interceptor (FOG) rules for Seattle restaurants?

Under SMC 21.16.310, any business with commercial kitchen plumbing fixtures and a King County Food Business Permit must install and maintain a grease interceptor and clean it per the manufacturer's specifications and whenever it is more than 25% full of grease and food waste. Emulsifiers, enzymes, and bio-additives are banned, and SPU says every interceptor must be professionally cleaned at least once a year. Non-compliance penalties range from $250 to $5,000, plus the City's sewer damage costs. King County Industrial Waste separately limits nonpolar FOG to 100 mg/L.

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Seattle & King County, WA Certified Backflow Testing & Grease Trap (FOG) Directory