Oklahoma licensed septic contractors

Oklahoma publishes its septic licensing through the Oklahoma DEQ. This is every record it holds, as pages you can navigate: 264 businesses and 290 individually licensed onsite professionals across 58 of 77 counties.

264

DEQ certified installers

A business the state has licensed for the work that installs onsite sewage systems and may inspect their own work.

Oklahoma counties with the most licensed businesses

All 77 Oklahoma counties

The number is how many licensed businesses give that county as their address. Greyed counties have none — 19 of the 77.

How Oklahoma regulates septic work

Oklahoma DEQ certifies installers and publishes the whole list. A certified installer may inspect their own installation and backfill without waiting for a DEQ inspector, which is why the certification is worth checking rather than assuming.

DEQ publishes the active list; an installer who has lapsed drops off it, so the list is the current state of play at the date it was read.

Records as published August 26, 2026.