Septic inspection when selling a house in Indiana

0 statewide rules and 1 local rule 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.

Local rules in Indiana (1)

Where	What	When	Rule set by
St. Joseph County	Septic system and well	Water test before closing; results given to buyer at least 3 days before closing…	St. Joseph County Department of Health

Private wells in Indiana

About 1,677,339 of Indiana’s 6,619,680 residents (25%) got their drinking water from a private well in 2015, by the USGS estimate. The 1 county with a whole-county rule listed here hold about 76,774 of them (5%); the largest by well users: St. Joseph County (76,774).

Source: USGS county water use 2015 (Dieter et al., 2018); 92 counties in the USGS table.

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

Indiana ranks 7 of 45 states and territories by people on private wells (USGS 2015). In 21 of its 92 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:

LaGrange County: 82% of 38,809 residents on a private well
Starke County: 77% of 22,958 residents on a private well
Carroll County: 71% of 19,856 residents on a private well
Kosciusko County: 70% of 78,620 residents on a private well
Steuben County: 70% of 34,372 residents on a private well
Jasper County: 68% of 33,470 residents on a private well
Pulaski County: 67% of 12,889 residents on a private well
Warren County: 66% of 8,269 residents on a private well

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.

Soils for septic drain fields in Indiana

Across the 92 counties with USDA soil survey data, 95% of rated land is “very limited” for a conventional septic drain field. Most limited: Benton County (100%), Henry County (100%), Huntington County (100%). Least limited: Posey County (73%), Knox County (73%), Washington County (74%).

Source: USDA NRCS Soil Survey Geographic Database (SSURGO), via Soil Data Access, rating “ENG - Septic Tank Absorption Fields”, read November 15, 2026. County-wide ratings, not a test of one lot.

How the neighbouring states compare

Indiana has 1 local rule. Of its 4 neighbouring states, 0 have a statewide rule at sale; a buyer moving across the line may meet a different rule. From our register of official rules:

Michigan: no statewide rule; 11 local rules (counties, cities or townships).
Ohio: no statewide rule; 5 local rules (counties, cities or townships).

State law bars local point-of-sale rules. IDOH: local ordinances on residential onsite systems that vary from the state rule are void from 1 July 2023. LaPorte and Blackford sale rules are treated as void. St. Joseph County's own page (archived 2026-09-23) still describes a narrower rule from 2024-07-01 (septic inspection in the St. Joseph Aquifer System, water test countywide); counted as published, its fit with IC 16-41-25-7 not decided. IC 16-41-25-7, IC 16-19-3-27.8 (from 2023-07-01)

Well water test: 1 lab on the Indiana certified drinking-water list (IDOH Water Test Facilities Application (in-state drinking water laboratories), layer data edited 2026-08-17) is marked as taking samples from homeowners or outside clients and certified for coliform bacteria. See certified well-water labs and testing advice in Indiana.

Other states: all states.