How much will it Cost to Empty a Septic Tank?

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Correctly maintaining a septic tank is one of the most crucial aspects of home maintenance and it’s essential that only certified septic tank companies or tradespeople are hired to empty them. When obtaining quotes through our website to have your septic tank emptied, you will only be dealing with fully accredited companies or contractors.

Process of Emptying a Septic Tank

In cases where there is no mains sewage system. A septic tank needs to be installed on a property for toilets, baths, showers, dishwashers and kitchen sinks to drain into, and it usually needs to be emptied once a year.

In most cases, your chosen contractor will have to drive a small tanker on to your property to empty your tank, meaning that clear access will be needed between the septic tank and the area where the truck is going to park.

Quotes for emptying a septic tank will normally include removing and treating approximately 1,000 gallons of sludge. Once the tank has been emptied, it will normally also be backwashed to ensure that any remaining solids are removed as well. Contractors who empty septic tanks usually offer the option of a once-off service offering or a regular maintenance schedule, and clients will be able to decide what will be best for them.

cost of emptying a septic tank

How Septic Tanks Work

Septic tanks make use of an outlet pipe that runs from the house into a soakaway or drainage field. A soakaway consists of slotted or perforated pipes that enable wastewater to permeate into the ground without causing any form of pollution.

The tank works by separating the waste into sludge, scum and separated wastewater, and the separated wastewater is what runs off into the soakaway system. Solids stay behind in the tank, which is why they need to be emptied out every so often.

Septic tanks that aren’t emptied as often as they should be can cause toilets to take longer to flush – and in more severe cases, waste from the tank can even backwash into your home. Overflowing septic tanks can also generate extremely high levels of carbon dioxide, hydrogen sulfide and methane, which pose serious health and environmental risks.

How Often Must a Septic Tank be Emptied?

Although it’s normally recommended that a septic tank be emptied once a year at minimum, various factors will affect the frequency that this task needs to be done.

Some of the main factors that will affect the frequency of having a septic tank emptied are its size, the amount of people living on the property, temperature and age of the tank and the amount of solids in it. Having the tank emptied regularly will help ensure that its lifespan is extended for as long as possible.

Proper Care and Maintenance

The beat way to care for a septic tank is to ensure that it is emptied regularly. Additional steps that can be taken to ensure its longevity are to avoid disposing of non-biodegradable items such as sanitary products, cigarette butts, any form of grease or oil, coffee grounds, any type of antibiotics, bleach or other harsh cleaning solvents into your home’s drains at any time.

Paper products should never be flushed into a septic tank either, unless they have been specifically formulated for this purpose.

It’s also recommended that shrubbery and tree roots growing close to the tank be monitored and removed as needed.

Approximate Costs of Emptying Septic Tanks

  • Having a small septic tank emptied can cost between £90 and £120, with the job taking around 30 to 45 minutes to complete
  • Emptying a medium sized tank can average between £125 and £160, and take approximately an hour
  • Having a large septic tank emptied could cost anywhere between £180 and £220, and the process can take up to two hours
  • Emptying an extra large septic tank could average from £280 to about £330, and it can take up to three hours to get the job done

Take the Guesswork out of Obtaining Quotes

If your home relies on a septic tank system, chances are that you already know how important it is to have it emptied regularly. If you have been struggling to find reliable and accredited contractors to do the job, we will be able to assist you. Simply complete our website contact form and we will have up to four accredited contractors get in touch with you as soon as possible.


1. Is it normal to have scum on top of a septic tank?

Yes. This scum layer consists of oil, fat and grease and the microbes in the tank will break it down over time. It usually won’t cause any issues unless it becomes too thick and hardens. If the scum has started hardening, it’s time to have the tank emptied as soon as possible.

2. Why must a septic tank be emptied?

While most of the sludge in a septic tank is broken down over time, not all of it will disappear. This causes it to accumulate, which is why it’s recommended that a septic tank be emptied at least once a year.

3. If a septic tank smells really bad, what is the cause?

In most cases, a foul-smelling septic tank is caused by biomass that has died off. This means that bacteria will have to be added to the tank as quickly as possible. One of the main causes of biomass that has died off in a septic tank is cleaning products that have been poured down the toilet or sink.

4. How will I know if my septic tank needs to be emptied?

The best way to determine when your septic tank needs to be emptied is to have it professionally inspected. The contractor will measure the levels of content inside the tank to determine how full it is. It’s also recommended to have your septic tank inspected once a year.

5. How long does it take to have a septic tank emptied?

In most cases, this job will take less than a day to complete. However, your chosen contractor will be able to provide you with a more accurate timeframe after seeing the size of your tank.

6. What can result in my tank needing to be emptied more regularly than once a year?

Flushing paper products that are not septic tank compatible will cause the tank to clog up quite quickly. Sanitary items such as pads and tampons should also never be flushed into these systems. If more people than average are staying on your property for any length of time, it will also cause the tank to fill up quicker than usual.

7. What type of paper is safe for septic tanks?

One of the best ways to find paper that will be safe for use in a septic tank is to look for brands that have been recommended for use in motorhomes. These products have been manufactured especially to break down quicker than regular types of toilet paper.