How Much Does a Septic Tank Cost?

April 01st, 2021

How Much Does a Septic Tank Cost?

How Much Does a Septic Tank Cost?

Before we dive into how much a septic tank costs, let's first understand what septic tanks are for and why you need them.

When you build a new home, you need to find out if you need a septic or if you can tie it into a city sewer. A city sewer pipes wastewater from your home to a waste treatment plant. A Septic tank is a large tank with a drain field. It is usually buried underground near your home. When the septic fills up, solids sink to the bottom, and liquids rise. If you are in the city, you probably hook into the city sewer. Homes in the country usually have septic tanks. Homes in the suburbs could have either, depending on the infrastructure.

How much does a septic tank cost - what is the cost to replace a septic tank?

The septic tank is filled with "good" bacteria that render the waste into a neutral liquid. When the liquid gets to the top of the tank, it goes into the drain field – a series of large pipes with holes in them that allows the liquid to leech out into the ground.

The Price of a New Septic Tank

A new septic tank can cost upwards of $10,000 and the cost will depend on which system you choose, the location, the soil quality, and more often than not the cost will be closer to $25,000. The easiest way to determine the cost of a new septic tank system is to get a few different quotes from different vendors and have them break down the process from installation to completion. Oftentimes the cost of a septic tank will be totally dependent on the system itself, the labor, and the construction costs that are required to build the system.

If you only need to repair or replace parts of the septic tank the cost will be significantly less. A new septic pump will run you anywhere from $600-$1,500 and an actual septic tank is typically twice that depending on the tank you purchase. You likely want to go with a concrete tank since they have the longest lifespan.

How Do Septic Tanks Work?

Here's How Septic Tanks Work - Each Component of a septic tank has different features and functionality to assist the septic tank, septic field and help the system work!

Considerations that Affect the Cost of Installing a Septic Tank

The cost of a septic tank varies depending on several factors, including tank size, location, and the number of bedrooms in the house.

Perc Test

Before you can install a septic tank, you must have the location of the tank perc tested. This test shows how much liquid the ground will absorb. If the location passes the perc test, you can have your septic installed in that location. If not, you'll have to move the septic location. The new spot will also need to be perc tested. You might have to move the house site if the land doesn't pass a perc test. The cost of a perc test varies from county to county and state to state.


In addition to the perc test, you might have to obtain a permit to install a septic system. This depends on your county and state laws. In some counties, you only need the perc test. The cost of the permit depends on your location and county fees.


If your chosen spot has rock, the contractor might need to blast it away to get a hole deep enough for the septic tank. You do have some other choices, such as installing a high-boy tank or putting the tank above the ground if your location allows for those types of tanks. The cost of blasting also depends on your location and whether your county and state require an additional permit to blast.


The septic tank size is based on the number of bedrooms in the house. Most three-bedroom, two-bath homes require a tank that is at least 1,000 gallons. Your contractor will let you know what the restrictions are for your state and county. The cost of the actual tank depends on its size.

Double Tanks

In some cases, where drainage isn't the best, or you are on a hill, you might be able to install a double tank. The waste goes into a small tank near the house, then is piped via gravity to the larger tank. You can expect to spend at least $2,000 extra for a double septic tank. The cost depends on the difficulty of installing both tanks, such as terrain and blasting requirements.

In cases where you'll need a pump to pump the waste from the smaller tank to the larger tank, the cost will be higher since you have to pay for the pump.

Water Table

If the water table is too high, you'll have to build up the drain field to be the proper distance from the water table. The cost varies depending on the cost of aggregate and labor in your area.

Septic Tank Installation - Tractor digging up a field for the septic tank and leech field system

Septic Installation

The contractors won't install your septic tank until the framing for the house is completed – at a minimum. Some contractors wait until the house is almost finished. Once a tank is installed, supply trucks won't be able to drive over that section of ground. It would end up costing more and delaying building if the trucks had to avoid part of the area around the house.

Septic Tank Truck installing a septic tank, repairing a tank, or getting the septic tank pumped in the front yard

Septic Tank Maintenance Costs

Once your septic is installed, you have to maintain it. The costs involved with maintenance are minimal, though the costs for pumping the tank vary widely from state to state. During the year, you should add beneficial bacteria to your septic tank. Some septic pumping companies recommend pumping every five years, while others recommend pumping every three years.

You should pump it based on usage. If you have a small family or live by yourself, you might pump the septic every five years. For a family of four to five, you should consider pumping the tank every three years. If your family has six or more, you should consider pumping the septic every one to two years.

When You Should Replace a Septic System

Your septic system can last for 25 to 30 years if you properly maintain it. The cost to replace it will be more than the initial installation. You need to account for inflation and the cost to remove the old septic system.

Signs You Need to Replace Your Septic System

You might see one or more of these signs to replace the septic system. You can always have it checked by a professional if you think you need to replace it.

  • Your pipes back up.
  • The toilet gurgles when you flush it, or it doesn't flush well.
  • You notice a foul odor in the house.
  • The tank overflows. You'll notice puddles in your yard when it hasn't rained.
  • Your well water becomes contaminated.

In some cases, you can replace only the part of the septic that is not functioning. In that case, the cost will be less.

If your septic tank is relatively new and you notice the pipes backing up, check the grease trap. If it becomes clogged and there are no clogs in the pipes from the house to the septic, you'll have some of the same symptoms you'll see for replacing the tank.

Septic Tank Options

If you have a high water table, hit bedrock, or have poor drainage, you can also look into different types of septic tanks, though all of them cost more than the normal concrete tank that sits below ground.

  • A mound septic system is one that uses an elevated mound of sand for the drain field. The materials to create the mound and the pump to pump waste uphill add to the cost of the tank.
  • A recirculating sand filter septic system uses a pump to push the waste through a sand filter and back to the pump tank. The waste is then dispersed through the ground.
  • A drip septic system uses drip tubing and a timer to release small doses. Extra costs include the dose tank and pump, plus running electricity to the pump. This type of system is effective if the perc test shows poor drainage.
  • An evapotranspiration system uses a drain field that allows liquid waste to evaporate from an open-air tank. This type of septic system is often found in areas that are very dry and don't have a lot of rain or snow.
  • The built wetland system uses a wetland tank to get rid of the waste. The tank contains bacteria, microbes, and plants, which treat the waste before it is emptied into the soil.
  • A chambered system uses perforated chambers around pipes in the sand. The chambers are made of plastic. However, they crush easily, so you have to be careful not to drive over the tank, though that is not recommended regardless of the type of tank you have.

Types of Septic Tanks

You can choose from several types of tanks. However, concrete is the best since it lasts for decades if properly cared for and doesn't have some of the problems that plastic and poly tanks or fiberglass tanks have. Because plastic and fiberglass tanks are so light, they can easily suffer damage during installation and can also move once they are installed.

The fourth type is stainless steel, though those tanks are no longer permitted in many locations because they eventually rust. Older homes might have stainless steel tanks. If so, it is recommended that you replace the tank, or if you are buying a home, have the seller replace the tank or negotiate the replacement cost off the price of the house.

Septic Waste - How Much Does a Septic Tank Cost to install or replace and how much does it cost to pump a septic tank

Final Thoughts on How Much a Septic Tank Costs:

If you're wondering how much a septic tank costs the best way to find out is to call three local companies, have them come out to provide you with a quote and a written explanation of the services they intend to provide step by step. This takes the guesswork out of the cost of installing a new septic system. The cost is an expensive one, though it's a necessary one.

Find your new home Search real estate and homes for sale
Share this post
Ryan Fitzgerald

Ryan Fitzgerald

Hi there! My name is Ryan Fitzgerald, and I am a REALTOR®. My goal is to help you learn more about real estate through our Real Estate Blog! Hopefully, you enjoyed the above blog post and it found a way to provide help or value to you. When you're ready to buy or sell a home of your own let us know here. Please feel free to join the conversation by dropping us a comment below.