Backflow Specialty contractors in Washington
Backflow specialty contractors install and service the backflow prevention assemblies that keep contaminants out of drinking water lines. Washington currently lists 84 Backflow Specialty contractors registered statewide.
5 Star Backflow Services INC
Backflow Specialty · Kirkland, WA
License #5STARSB785RZ · $6,000 bond
A R Brown Backflow Testing
Backflow Specialty · Lynnwood, WA
License #ARBROBB760OF · $6,000 bond
A-Bat
Backflow Specialty · Everett, WA
License #BAT****785KB · $6,000 bond
Aaa Backflow Ass TS & Serv LLC
Backflow Specialty · Everett, WA
License #AAABABA744DU · $6,000 bond
Aaa Backflow Asy Tstng/Svc LLC
Backflow Specialty · Camano Island, WA
License #AAABABA781PQ · $6,000 bond
Aaa Fire Protection INC
Backflow Specialty · Seattle, WA
License #AAAFIFP777PZ · $6,000 bond
Aacra Backflow Testing/Repair
Backflow Specialty · Snohomish, WA
License #AACRABT795PD · $6,000 bond
Ace Backflow Only
Backflow Specialty · University Place, WA
License #ACEBABO770M8 · $6,000 bond
Adagio Backflow Testing
Backflow Specialty · Bellingham, WA
License #ADAGIBT759RA
Advance Testing & Service INC
Backflow Specialty · Marysville, WA
License #ADVANTS782PL · $6,000 bond
Affinity Home Solution
Backflow Specialty · East Wenatchee, WA
License #AFFINHS779J1 · $6,000 bond
Affordable Washingtn Bkflw LLC
Backflow Specialty · Cle Elum, WA
License #AFFORWB789JR · $6,000 bond
Always Testing INC
Backflow Specialty · Mountlake Terrace, WA
License #ALWAYTI782L7 · $6,000 bond
Apex Backflow Services
Backflow Specialty · Puyallup, WA
License #APEXBBS776P7 · $6,000 bond
Archer Construction INC
Backflow Specialty · Kent, WA
License #ARCHECI768PS · $6,000 bond
Awa Backflow
Backflow Specialty · Malott, WA
License #AWABAB*780NA · $6,000 bond
Axis Backflow Testing
Backflow Specialty · Lake Forest Park, WA
License #AXISBBT782DA · $6,000 bond
Backflow Assembly Sltns INC
Backflow Specialty · Kingston, WA
License #BACKFAS760K4 · $6,000 bond
Backflow For Business
Backflow Specialty · Gig Harbor, WA
License #BACKFFB743C5 · $6,000 bond
Backflow Johnny
Backflow Specialty · Colbert, WA
License #BACKFJ*779KD · $6,000 bond
Backflow Tri-Cities LLC
Backflow Specialty · Pasco, WA
License #BACKFTL774LZ · $6,000 bond
Backflows Northwest INC
Backflow Specialty · Bellevue, WA
License #BACKFNI792QW · $6,000 bond
Ballance Backflow Inspection
Backflow Specialty · Colville, WA
License #BALLABI754M1 · $6,000 bond
Bat Pro Backflow Services LLC
Backflow Specialty · Blaine, WA
License #BATPRPB786LP · $15,000 bond
Cities with Backflow Specialty contractors
Built from Washington State L&I public records, updated Aug 13, 2026. No star ratings or reviews — verification only.