Oklahoma rules (OAC 252:641-10-3) require the installer of a new aerobic system to maintain it for two years at no extra cost to the owner, including the inspection and testing duties listed in the rule.
After those two years, the owner is responsible for keeping the system working — by maintaining it themselves or by hiring someone. A forever paid maintenance contract is not a statewide mandate.
Some cities add local paperwork. Edmond, for example, describes yearly verification of continued professional inspections after the builder two-year period. Check your city; do not assume every town matches Edmond.
Optional service agreements still make sense for many owners: chlorine residual, sludge depth, spray-head function, and faster help when an alarm trips.
Keep written notes. A later buyer, a city clerk, or a repair tech will want dates, sludge readings, and who did the work. This directory does not store those records for you.
If you hire help, ask what each visit includes and whether they cover your Oklahoma address. Installation credentials and ongoing maintenance are related, but they are not the same promise.
Quick answers
Does Oklahoma require a paid contract forever?
No. After the installer’s first two years, the owner may maintain the system or hire someone.
Does an Edmond mailing address prove the city rule applies?
No. Confirm the property is inside Edmond city limits before applying that local note.
Use the directory as a starting point.
Ask the company to confirm your system type, exact task, property coverage, timing, and price. A directory record does not replace an on-site evaluation.