O'Neill Plumbing

Category

Plumbing

Address

6056 California Avenue Southwest, Seattle, WA 98136

Website

oneillplumbing.com

Data checked

November 6, 2026 (OpenStreetMap)

Before You Hire

Facilities usually schedule plumbers yearly for backflow tests and water heaters, plus repairs as needed. Ask:

• Do you take commercial work, and do you service buildings like ours?
• Can you send a certificate of insurance naming us as additional insured?
• Are you licensed in this state, and may we have the license number?
• Do you have certified backflow testers, and do you file reports with the water utility?
• Do you offer 24-hour emergency service, and what is the call-out fee?

All 8 questions to ask →

Hiring Tips

• Label every main and zone water shutoff before you need them.
• Your water utility usually sets the backflow test deadline; keep its notice on file.

Getting several quotes? Line them up in the quote comparison tool and check the contract checklist before you sign.