The most reliable way to find a certified backflow tester is to check your local water utility's approved or registered tester list, since many utilities only accept test reports from testers they've specifically recognized. A general search can surface plenty of companies, but not all of them may be currently certified or on your specific utility's list, so that extra verification step matters.
Start With Your Water Utility, Not a Search Engine
Because backflow testing requirements and approved-tester programs are administered locally, your water utility (or the municipal cross-connection control program) is the authoritative source for who's allowed to perform your test. Many utilities publish an approved tester list on their website, and some maintain their own online lookup tool. The EPA's cross-connection control program page explains why these programs sit at the state and local level rather than under one national registry — which is exactly why "certified backflow tester near me" doesn't have a single national database to search.
What Certification to Look For
Most backflow testers hold a certification such as ASSE 5110, which is a widely recognized credential for backflow prevention assembly testers, though some states or municipalities issue or require their own certification in addition to or instead of ASSE credentials. Certification typically requires completing an accredited training course and passing both a written and hands-on exam covering how to test various assembly types (double check, RPZ, and others) using calibrated equipment. When vetting a tester, ask which certification they hold and confirm it's current — certifications typically require periodic renewal.
Questions to Ask Before Booking
Are you on [Utility Name]'s approved tester list? This is the single most important question, since a technically certified tester who isn't on your specific utility's list may still have their report rejected.
Is your test gauge currently calibrated? Ask for the calibration date or certificate. Utilities can reject results from equipment that's overdue for calibration.
Do you handle report filing, or is that on me? As covered in our report filing guide, this varies by company and by utility.
What's included if my assembly fails? Understanding upfront how repair quoting works avoids surprises — see what happens after a failed test.
What's your pricing for my assembly type and count? See our backflow testing cost guide for typical ranges and what drives price differences.
Residential vs. Commercial Testers
Some backflow testing companies focus primarily on residential irrigation assemblies, while others specialize in larger commercial and fire-line systems that may require different tools, insurance, or experience with more complex assembly configurations. If you manage a commercial property with multiple assembly types, it's worth confirming the tester has direct experience with your specific configuration, not just general certification.
A Note of Caution
Because requirements and approved lists genuinely differ by location, be cautious of any company that claims blanket "certified everywhere" status without being able to point to specific state or local credentials. A legitimate tester should be able to tell you exactly which certification they hold and should have no hesitation confirming they're on your utility's approved list — if they're vague on either point, verify independently with your water utility before booking.
FAQs
Is ASSE 5110 accepted everywhere? It's widely recognized, but some states and utilities have their own additional or alternative certification requirements. Confirm what your specific water utility accepts.
Can a plumber test backflow assemblies without separate certification? Generally no — most water utilities require backflow-specific certification distinct from a general plumbing license, since testing requires specialized calibrated equipment and training.
How do I confirm someone is really certified, not just claiming to be? Ask for their certification number and cross-check it with your water utility or the certifying body directly, rather than relying solely on the tester's own representation.
How to Choose and Verify a Backflow Testing Company
Before hiring, confirm the tester holds a current, relevant certification — typically ASSE 5110 or your state's equivalent — and appears on your water utility's approved tester list. Also confirm their gauge kit's calibration is current, since that's often the detail that determines whether your utility accepts the resulting report.
This directory is an independent, source-backed listing of public records. It does not certify or endorse any backflow testing company listed. Always verify certification and approved-list status directly with your local water utility before booking.