Septic System Cost Calculator
Estimate septic system installation cost by type and lot size.
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Septic System Cost
What This Calculator Does
The Septic System Cost Calculator estimates the cost of installing a new septic system or replacing an existing one based on your home size, soil type, and 2026 US national average pricing. Enter the number of bedrooms and select the system type to get a cost range.
Septic systems are essential for homes not connected to municipal sewer. The cost varies significantly by system type - conventional gravity systems are the most affordable, while advanced treatment systems and mound systems can cost two to three times more, especially in areas with poor soil conditions.
How to Use
- Enter the number of bedrooms in your home (determines septic tank size needed).
- Select the system type - conventional gravity, pressure distribution, or aerobic/mound.
- Select soil type - good drainage (sandy/loam) or poor drainage (clay/high water table).
- Click "Calculate" to see the estimated cost range.
- Add $500-$2,000 for perc testing before installation.
Reference Table
| Bedrooms | Conventional | Pressure Distribution | Aerobic/Mound | Tank Size |
|---|---|---|---|---|
| 2 Bedroom | $3,500-$7,000 | $5,000-$12,000 | $8,000-$18,000 | 750-1,000 gal |
| 3 Bedroom | $4,000-$10,000 | $6,000-$15,000 | $10,000-$22,000 | 1,000-1,250 gal |
| 4 Bedroom | $5,000-$13,000 | $8,000-$18,000 | $12,000-$28,000 | 1,250-1,500 gal |
| 5+ Bedroom | $7,000-$18,000 | $10,000-$22,000 | $15,000-$35,000 | 1,500+ gal |
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