Septic inspection when selling a house in Arizona

1 statewide rule and 0 local rules from official sources.

General information, not legal advice. This is our summary of the official rule as we read it. The ordinance or code and the health department decide: confirm with them before you list, sign or close.

Statewide: septic system at sale

Every property served by an on-site wastewater treatment facility. The buyer files a Notice of Transfer within 15 calendar days after the transfer: with ADEQ for systems completed before 2001, otherwise with the county agency ADEQ has delegated.

QuestionWhat the official text says
Triggered bysale, transfer
Source: apps.azsos.gov
DeadlineInspection within six months before the date of property transfer; Report of Inspection and facility documents given to the transferee before transfer; transferee files Notice of Transfer within 15 calendar days after transfer
Source: apps.azsos.gov
Who arranges itThe person transferring the property (the seller) retains a qualified inspector
Source: apps.azsos.gov
How long a report is validThe inspection must be done within six months before the transfer
Source: apps.azsos.gov
Exemptions
  • Facility with a Discharge Authorization not yet put into service before the transfer (Notice of Transfer still required)

Source: apps.azsos.gov
In force sinceJanuary 1, 2002
Source: apps.azsos.gov
Official ruleA.A.C. R18-9-A316 (Arizona Administrative Code, Title 18, Ch. 9, Supp. 25-2)

Checked on November 13, 2026: read in a web-archive copy of the official page (the live site was blocked from our connection).

Read the rule (apps.azsos.gov)

Programme page (azdeq.gov)

Private wells in Arizona

About 218,170 of Arizona’s 6,828,065 residents (3%) got their drinking water from a private well in 2015, by the USGS estimate.

Source: USGS county water use 2015 (Dieter et al., 2018); 15 counties in the USGS table.

Where private wells (and usually septic systems) are most common

Arizona ranks 36 of 45 states and territories by people on private wells (USGS 2015). In 0 of its 15 counties more than half of residents drink from a private well; homes there usually also treat wastewater on site, so a septic check and a well test tend to come up together at sale. The highest shares:

USGS county water use 2015 (Dieter et al., 2018). The USGS table counts well users, not septic systems; no national county count of septic systems exists.

How the neighbouring states compare

Arizona has a statewide rule. Of its 5 neighbouring states, 1 has a statewide rule at sale; a buyer moving across the line may meet a different rule. From our register of official rules:

  • New Mexico: statewide septic system rule at sale.
  • California: no statewide rule; 1 local rule (counties, cities or townships).
  • Colorado: no statewide rule; 10 local rules (counties, cities or townships).

Testing a well? See certified well-water labs and testing advice in Arizona.

Other states: all states.