How Much Does a Septic Tank Cost?

A septic tank costs between $500 and $2,500, depending on what size tank you need. An entire septic system typically costs between $3,615 and $12,408, with a national average price of just over $8,000.

If you already have a septic system in place and only need to replace the tank, your costs will depend on a number of factors, beginning with the size of the tank. Here’s what you might expect to pay for just the tank itself, based on tank size.

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Materials

The material your septic tank is made of affects its price.

Labor

Labor costs vary by location and generally constitute 50% to 70% of the total job price. For a typical three- or four-bedroom home, installation generally ranges from $1,500 to $4,000. Excavation to install your septic system will likely add $1,500 to $6,300 to labor costs.

System type

• Anaerobic vs. aerobic septic system. Anaerobic systems have little or no oxygen in the tank^[0]

  University of Illinois Extension . How Treatment Systems Work. Accessed Jan 9, 2025.

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  . They are the less expensive option, generally costing between $3,000 and $8,000. Aerobic systems, which inject oxygen into the tank and are used in homes on small lots or with high water tables, are more efficient but cost between $10,000 and $20,000^[0].

• Alternative systems. If a traditional septic system won’t work on your specific property, you may have to go with an alternative system, such as a mound, drip, chamber, sand filter, evapotranspiration or build wetland setup. Alternative systems tend to be more costly than traditional systems. For example, a mound system can cost as much as $20,000.

Surveys and permits

Before installing a new septic system, you’ll need a land survey from a licensed land surveyor, which usually costs between $330 and $900.

Permit laws vary by location, but septic permits may run as much as $450 to $2,300.

Testing

A percolation test checks how your soil absorbs water and helps determine which type of septic system is best for your property. It typically costs $700 to $2,000.

Leach field installation

Putting in a leach field (also known as a drain field), which is a type of trench that transports wastewater back to the soil, typically costs between $5,000 and $12,000.

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On average, septic systems last 15 to 40 years. With proper care and maintenance, however, they may last longer^[0]

• Don’t put items into your sink or toilet that could clog your septic system. These items include feminine hygiene products, baby wipes, diapers, coffee grounds, cigarettes, cat litter and grease.

• Don’t put items that could damage or “kill” your septic system into your sink or toilet. These items include gasoline, household chemicals, oil, paint, anti-freeze, pesticides or large quantities of household detergents and soaps.

• Don’t overuse water. When you conserve water, your septic system won’t have to work so hard. Additionally, opt for high-efficiency plumbing appliances, repair household plumbing leaks and stagger the use of appliances to avoid straining your septic system.

• Don’t use a garbage disposal unless absolutely necessary. Reducing or eliminating garbage disposal use helps reduce the volume of damaging grease, fats and other solids that get into your system.

• Protect your leach field. Plant trees away from the field, as roots can clog up the field and cause system failure. Additionally, don’t put anything heavier than a lawnmower on your field, and direct excess water from drains, heavy rainfall and irrigation away from the leach field area.

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Plan to have your septic system professionally inspected and your tank pumped out about every three to five years (or as recommended by your municipality and/or service provider). The professional inspection should let you know when the pumping is necessary. This scheduled routine maintenance should cost between $250 to $500, which might feel like a lot, but it can prevent costly repairs that could run tens of thousands of dollars.

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• Compare multiple quotes from trusted, reputable contractors before committing to a purchase.

• Purchase materials on your own instead of through the contractor to avoid price markups.

• Gather your own soil samples and coordinate testing yourself rather than pay a technician to collect soil samples.

• If you have the required skills, prepare your land yourself rather than hiring a professional. This work might include backfilling and other prep work.

• Confirm code compliance and arrange for necessary permits yourself rather than having your contractor do this for you.

• If practical, arrange to have work done during the off season, when you may be able to get discounts and lower rates.

• If the need for a new septic tank is due to damage to your system from a specific event, check with your homeowner’s insurance company to see if that damaging event is covered, and if your policy might pay for some or all of your tank replacement costs.