The reference for residential septic systems
Septic answers you can check — sized, priced and sourced.
Calculators that show their math. Costs with the year and source behind every number. State rules taken from the regulator, not guessed. Built for homeowners, buyers and rural property owners.
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- ✓ Methodology shown on every calculator
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Calculators
All calculators →- Septic Tank Pumping Frequency CalculatorYears between pump-outs from tank size, household size and garbage disposal.1,000 gal + 4 people ≈ 2.6 yrs
- Septic System Cost CalculatorInstalled cost by system type from EPA figures in today's dollars, with permit fees and a market cross-check.Conventional: ~$7,000–$14,000
- Septic Tank Size CalculatorTank size from bedrooms, people, disposal and your state's code minimum — with the math shown.Typical: 1,000–1,500 gal
Guides
- CostsHow Much Does an Aerobic Septic System Cost?Unit, drain field, power and service costs, with a 20-year cost comparison.Complete system: $10,000–$20,000
- CostsHow Much Does Drain Field Replacement Cost?Field cost by type, how soil sets the size, repair options rated by evidence, and permits.Conventional field: $4,600–$10,000+
- CostsHow Much Does a Mound Septic System Cost?EPA's itemized mound estimate in today's dollars, with operating costs and when a mound is required.3 BR: ~$19,600
- CostsHow Much Does a Perc Test Cost?Official evaluation fees from 10 states, who performs the test, and what a failed lot means.Official fees: ~$75–$750
- CostsHow Much Does a Septic Inspection Cost?Inspection prices by type, what a full inspection includes, and the states that require one at sale.Home-sale inspection: $350–$1,200
- CostsHow Much Does It Cost to Install a Septic System?Installed cost by system type in today's dollars, real permit fees, and why soil decides the price.Conventional: ~$7,000–$14,000
- CostsHow Much Does It Cost to Pump a Septic Tank?EPA's pump-out average in today's dollars, what raises the price, and cost per year by household.Typical: ~$350 (market $255–$600)
- CostsHow Much Does It Cost to Replace a Septic Tank?Tank-only vs. full-system replacement, when a tank fails under state rules, and abandonment rules.Tank only: ~$2,000–$7,500
- PumpingHow Often Should You Pump a Septic Tank?The 3–5 year rule explained, with the full chart by tank size and household, and the signs it's time.Typical: every 3–5 years
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Pages are written with AI assistance. Every number, fee and rule is then checked against the primary source cited at the bottom of the page (EPA, state regulators, university extensions, NSF, manufacturer spec sheets) and reviewed by the site editor. Each page shows when it was last reviewed. Read the editorial policy.