What size septic tank do I need for a 3 bedroom house?

Most states require a minimum 1,000-gallon tank for a 3-bedroom home. If you have a garbage disposal, many states require a 50% larger tank (1,500 gallons).

How often should I pump my septic tank?

The general recommendation is every 3-5 years, but this depends on tank size, household size, and water usage.

What affects drainfield size?

Drainfield size is primarily determined by daily wastewater flow and soil type. Clay soils require larger drainfields due to slower absorption, while sandy soils can use smaller areas.

Do I need a permit for septic installation?

Yes, permits are required in all 50 states for new septic system installations.

Calculator States Guides Articles FAQ

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Septic codes changeat every state line.

Tank size, drainfield specs, permits, and inspection rules vary widely. Pick your state for the requirements that actually apply.

All 50 states covered, with regulatory contacts and direct links.

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State pages cover regulations and minimums. To turn those into a number for your specific home, drop into one of the four calculators and read its companion guide.

Tank Sizing

Calculator

Septic Tank Size Calculator

Get tank-size recommendations based on bedrooms, fixtures, and your state code.

Companion guide

How Septic Systems Work

The foundational guide. What every septic owner should understand before sizing or budgeting.

Drainfield

Calculator

Drainfield Size Calculator

Calculate the absorption area you need, by soil type and water usage.

Companion guide

Understanding Your Drainfield

How drainfields work, the five major types, and how to keep one alive for 25+ years.

Cost Estimating

Calculator

Septic System Cost Estimator

Total install cost (tank, drainfield, permits, and labor) for your bedroom count and soil.

Companion guide

Septic System Costs

A full cost breakdown: install, ongoing maintenance, common repairs, and where money goes.

Pump Schedule

Calculator

Pump Schedule Calculator

Personalized pumping interval based on tank size, household, and habits.

Companion guide

Septic System Maintenance

The full maintenance playbook: schedule, do’s and don’ts, drainfield protection.

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Plug your state into a calculator + read the matching guide

.css-1t9gcl2{color:#122F6F;display:block;}Septic codes change.css-lpgtc6{color:#273147;display:block;}at every state line.

Plug your state into a calculator + read the matching guide

Septic codes changeat every state line.

Septic codes changeat every state line.