How Much Does It Cost To Empty A Septic Tank?

Want to find out the cost of emptying a septic tank and cleaning a septic tank?

This price guide looks at all you need to know about cleaning and emptying your septic tank, including rules and regulations, the costs of labour, frequently asked questions and everything you should consider.

Why not check it out?

septic tank entrance


Depending on the complexity of the job, this usually takes: 0.5-1 day


How Much Does Cleaning and Emptying a Septic Tank Cost?

The average price a tradesperson would charge to professionally clean and empty a septic tank is generally around £200. However, this cost will vary depending on the size, scale and time it would take to clean your septic tank.

There are many cost-affecting factors to consider when budgeting to have your septic tank cleaned professionally, such as the type of septic tank, either single or multi-chamber, you have and how easy it is to gain access.

The fee’s involved with hiring a qualified drainage engineer to empty and clean your septic tank, will cover the removal of waste, any repairs needed and a chemical cleaning service.

Clearance costs will vary depending on the size of your septic tank and the number of people that live in your household. The volume of waste that requires emptying and cleaning will have an impact on the amount of time it takes to complete the job.

As with other tradespeople, many drainage tank operators will likely charge either an hourly or daily rate.

The longer the job takes to complete, will affect how much you pay to empty and clean your septic tank.

Keep in mind that emptying and cleaning your septic tank is not just a one-off treatment and should be frequently maintained twice per year, depending on the volume of waste your household accumulates.

Emptying a Septic Tank Prices

Below is a table for you to compare the variation in cost when hiring a professional septic tank cleaning company to carry out the emptying and cleaning service for you.

Please note, these prices are estimated and should be used as a guideline, many cost-affecting factors could cause these prices to increase or decrease accordingly.

4,500 Litre Tank Single Chamber 1-2 times a year £90-£130
8,500 Litre Tank Single Chamber 1-2 times a year £150-£200
12,500 Litre Tank Multi Chamber 1-2 times a year £220-£250
17,500 Litre Tank Multi Chamber 1-2 times a year £260-£300
Want a custom price?

Post your job

Labour Costs & Timescales

Labour costs are usually including in the overall price and will depend on how large the septic tank is.

Again, the duration of emptying and cleaning a septic tank depends on the size, but check out the table below for some average time scales:

Small – 4,500L 45 mins
Medium – 8,500L 1 hour
Large – 12,500L 1.5 hours
Extra Large – 17,500L 2-3 hours
Want a custom price?

Post your job

For an in-depth look at how industry trends could affect labour costs, you might find our Building Industry Statistics page useful.

Find Tradespeople, compare up to 3 quotes!
It’s FREE and there are no obligations

Cost Factors of Cleaning and Emptying a Septic Tank

The main attributing factor for how much you pay to clean and empty a septic tank is the size. For a smaller tank, you can expect to pay as little as £90, but an extra-large tank can cost up to £300.

The type of tank can also contribute to the overall cost. If you have a single chamber septic tank, it’s likely to cost less as they’re less complicated, whereas the multi-chamber septic tanks may cost a little more.

What’s Involved with Cleaning and Emptying a Septic Tank?

Hiring a professional septic tank cleaning company to tackle the job of emptying your septic tank is the best way to maintain a good standard of waste removal and water hygiene.

The tank operator will visit your property to assess the scale and complexity of the job, inserting a special hose into your septic tank that is designed to suction out all of the accumulated waste.

An advantage of having a professional team to carry out the emptying process for you means that you do not have to deal with the excess waste and bad smells. Instead, they will safely and effectively remove the wastewater and sludge, disposing of it correctly.

Once the tank has been appropriately emptied and all waste disposed of, the septic tank specialist will usually perform what is known as a backwash. The backwash is intended to remove leftover solids that have not yet been digested by the microorganisms that live inside the tank chamber.

Once the tank is empty and clear of any waste, the operator will inspect the inside of your septic tank chamber for any cracks or damaged areas. You must have any repair work completed following the removal of waste to ensure that your drainage system does not fail.

The tank operator may run a test with some water by flushing a toilet inside your home to check that the tank is in working order and drains correctly.

Depending on your local authorities’ regulations for disposing of hazardous waste, your drainage engineer will likely dispose of the septic tank wastewater at a local waste-treatment plant.

The septic tank specialist will then use professional chemical cleaning products to remove any leftover scum thoroughly and ensure that your tank is safe and ready for future use.

These specialist products are intended for use with septic tank systems. Your qualified tradesperson will then advise you on the recommended maintenance for your septic tank system and how you can monitor the condition of your tank to ensure it is fit for everyday use.

Ask a Trade
Got a question that only a tradesperson can answer? We have thousands of trades ready to answer any question you may have.

Ask your question

New Septic Tank Regulations

In January 2020, there was an update on septic tank regulations in the UK. The new laws now mean that you won’t be able even to sell your house legally if your septic tank isn’t compliant.

The new legislation affects all properties that have a septic tank that discharges into watercourses or surface water. If this affects you, you’ll need to divert your septic tank to a drainage field or replace it with a sewage treatment before you sell your property.

If you replace a septic tank, it must meet the British Standards (BS EN 12566-1), and it’s illegal to install any septic tank that doesn’t meet this specification.

Your replacement tank must also be the correct size for the property and habitants and must require the installer to check these details before installation.

You must empty and clean your tank frequently, and it cannot exceed the maximum capacity. It can only be emptied by a registered waste carrier, to check this you can ask for their waste carrier’s certificate.

When selling your property, you must now inform the new owner (in writing) that they’ll be responsible for a septic tank and its discharge. The information has to contain:

  • Full explanation of the septic tank and drainage field.
  • Position of tank and drainage field.
  • Specify any changes made to the septic tank or drainage field from the original design.
  • Details of any mandatory routine maintenance.
  • Include records of all maintenance, (you have to keep any records for 7 years).

New regulations may mean that you need to upgrade and install a new septic tank, failure to do so may result in you being unable to sell your property.

DIY Cleaning and Emptying a Septic Tank

Emptying and cleaning your septic tank yourself is not a job for any DIY-er. Even if you feel competent, the process can only be carried out by a professional, licenced septic tank engineer.

As of January, the 1st 2020, new legislations states that it is a criminal offence for anyone who is not a licenced waste disposal professional to empty a septic tank. This is because it is illegal to dispose of toxic waste incorrectly as it poses a significant health risk for people, animals and the environment.

Under no circumstances should you attempt to dispose of any septic tank wastewater yourself, or else you could face a hefty fine and up to 6 months imprisonment.

Not only is emptying a septic tank yourself illegal, but it is also extremely dangerous. Pollution is the number one cause of concern when emptying a septic tank, as you are exposing yourself and the environment to hazardous septic waste.

Larger and multi-chamber septic tanks may require a professional to climb inside in order to clean it thoroughly.

Never, under any circumstances, should you attempt to climb inside a septic waste tank as you are at risk of severe health complications and even life-threatening conditions.

The updated Environmental Permitting Regulations state that there is a specific way to dispose of any toxic wastewater correctly so that no animals, habitats and wildlife are harmed in the process. We suggest leaving it to the professionals.

How Often Should I Clean and Empty my Septic Tank?

Emptying and cleaning your septic tank is a job that should be carried out at least once per year. This is because the purpose of a septic tank is to collect and naturally treat household wastewater, holding until solid debris forms a layer of sludge in the bottom of its chamber.

Microorganisms slowly decompose the solid layer, allowing other layers of filtered wastewater to flow away quickly into the sewer systems. If you do not regularly empty your septic tank, you could face drainage issues in your homes, such as blocked drains, water pollution, foul-smelling odours and nasty back flows of waste.

emptying septic tank 3

A common misconception amongst homeowners is that they only need to have their septic tank cleaned or pumped once and it will last for many years. What most people do not realise is that a healthy septic tank system relies on adequate maintenance and care for optimum performance.

As a general rule, we recommend emptying your septic tank yearly. However, as we previously mentioned, this could vary depending on how frequently your septic tank accumulates waste.

Smaller households may only require assistance cleaning and emptying a septic tank once every 2-3 years, while larger and multi-tank homes will need treating more often. If you have to empty your tank more than once a year, the price you pay for emptying and cleaning your tank will go up annually, so instead of paying £150 for emptying the tank once a year, you may have to pay £300 if you empty the tank twice a year.

You may be wondering how you can monitor whether your septic tank is getting full or requires your attention.

Thankfully, there are many signs that you can watch out for that indicates your septic tank needs emptying. Puddles of water are the number one recognised sign that your septic tank is full.

These pools will often be located around your septic tank’s drainage system outlets and imply that your tank is full or overflowing.

Blocked or lack of drainage in your home is another common sign that your septic tank may be full, along with gargling and bubbling sounds coming from inside the drain.

Often, homeowners will recognise a foul-smelling odour coming from their sinks and toilets, which indicates that the waste is not clearing correctly, or a blockage is present.

Finally, if the septic tank becomes so full that it fails to function correctly, you will likely have a backup of sewage inside your home. This is a cause for concern, and you should immediately contact your local septic tank drainage specialists for an urgent visit to your home.

Hiring a Septic Tank Expert Checklist

As with other projects, there are specific steps you should consider taking when hiring a qualified septic tank specialist. Below are our tips for hiring a septic tank expert.

  • Research all local septic tank drainage companies to compare a list of their services.
  • Gather multiple quotes in order to get the best price and service for your needs.
  • Never pay the full amount up-front and always get a written copy of your quoted price and service breakdown.
  • Check that your septic tank engineer is qualified and licenced to carry out the work along with disposing of the waste correctly.
  • Ask your engineer where the waste will be disposed of once the job has been carried out, to ensure that they are following local legislations.
  • Enquire about regular maintenance and additional services for future cleaning.


Do You Have To Empty A Septic Tank?

Yes, regularly. In order to maximise the performance of your septic tank, it should be cared for with the appropriate maintenance. If looked after correctly, your septic tank can be an excellent investment that lasts up to 40 years.

What Happens If A Septic Tank Isn’t Emptied?

If a septic tank isn’t emptied, the layer of solids will build up inside the tank chamber, causing an overflow in the waste capacity. Over time, the sludge and wastewater will back up and have no choice but to make their way into your home.

What Type Of Cleaners Are Safe With A Septic Tank?

There are many specially formulated cleaners available that are designed to work with septic tank systems. Most ammonia-based products are also safe to use as well as water-based disinfectants and toilet cleaners.

What Toilet Paper Is Safe For A Septic Tank?

A good quality soft-tissue toilet paper is recommended for use with septic tank systems. This is to prevent the paper from clogging and blocking up your septic tank chamber.

How Long Does A Septic Tank Last?

If regularly cared for and inspected, your septic tank system will likely last anywhere between 15 and 40 years. Proper maintenance is the key to promoting the longevity of your septic tank system.