The share of new single-family homes built with individual wells and septic systems increased in 2025 compared to the previous year. According to NAHB’s analysis of the Census Bureau’s Survey of Construction (SOC), approximately 10% of single-family homes started in 2025 were served by individual (private) wells, and 17% relied on individual septic systems.
Nationally, most new homes were connected to public water systems, which include community or shared supplies/wells. The remaining 10% were built with private wells, increasing one percentage point from the previous year.
The share of private wells significantly differed by Census division. In New England, where median lot size is double the national median, 42% of new single-family homes relied on private wells, making it the division with the highest rate in the nation. The East North Central division followed with 26%, while the Middle Atlantic stood at 15%. The South Atlantic region also exceeded the national average, with 13% of new homes using private wells. In stark contrast, private wells were uncommon in the East South Central, West South Central and Pacific divisions, where they accounted for one to two percent of new homes started.
For sewage disposal, 83% of new single-family homes in 2025 were connected to public sewer systems, which include community or shared sewage/septic systems. The remaining 17% utilized individual septic systems, one percentage point higher than the previous year. As with private wells, the usage of individual septic systems varied significantly by region.
New England led the nation with 52% of new homes using individual septic systems. The East South Central (33%), East North Central (27%), and South Atlantic (23%) divisions also reported shares above the national average. In contrast, lower usage was recorded in the Mountain (9%) and West North Central (9%) divisions, while the Pacific and West South Central divisions had the smallest shares, at 5%, respectively.
Compared to 2024, five of the nine Census divisions experienced an increase in the use of individual septic systems with four of the divisions falling below the national average of 17%. East South Central in particular saw a large increase of 8-percentage points as it surpassed East North Central as the division with the second largest share of individual septic systems. New England remained the largest shareholder with 52%, a 3-percentage point increase. Only Pacific and East North Central saw declines in shares of 2- and 1-percentage points, respectively.
