Drain field replacement cost (2026)

The drain field, also called a leach field, is the network of buried perforated pipes or chambers that spreads treated water from the septic tank into the soil. When the soil clogs and stops absorbing water, the field fails and usually has to be rebuilt in a new area of the yard.

Figures are 2026 national estimates compiled from published cost guides such as Angi, HomeGuide and This Old House. Prices in high-cost metro areas often run above these ranges.

Typical costs

What affects the price

• Soil. The perc test decides how large the field must be and whether a conventional field is allowed at all.
• Home size. More bedrooms mean a larger field.
• Space and slope. Tight or steep lots may need engineered designs.
• Groundwater and rock, which raise excavation costs or require a mound system.
• Local health department rules, which vary widely from county to county.

Signs of a failing drain field

• Soggy ground or standing water over the field
• Bright green, fast-growing grass over the trenches
• Sewage odors in the yard
• Slow drains and backups even after the tank is pumped

Repair before replacing

Not every problem means a new field. A crushed pipe, a clogged distribution box or roots in one line can often be repaired. Rejuvenation treatments may help a field that is slow but not completely failed. A septic inspection, usually $150 to $450, is the way to find out.

Protect a new field

• Pump the tank every three to five years for a typical household.
• Keep vehicles and heavy equipment off the field.
• Spread out laundry loads and fix running toilets, which flood the field with water.