• Skip to main content
  • Skip to primary sidebar

HomeownerCosts

Compare Quotes & Save up to 33%

Compare Quotes & Save up to 33%

Get up to 3 quotes from pros in your postcode
1. Do you require a local septic tank installer?*
Powered by Bark.com

Septic Tank Cost 2025: Replacement & Installation Prices UK

If you’ve never heard of a septic tank, you probably live in a town or city where your solid and liquid waste discharges down the drain. If you live in the country, you may not have this luxury. So, the only way to safely discharge waste from toilets, baths, showers, sinks, washing machines, etc. is to drain into a septic tank and let nature take its course.

Topics

  • How Much Is A Septic Tank? (including labour cost)
  • Factors To Consider For The Job
    • Septic Tank Installation
    • Purchasing 
  • How Do Septic Tanks Work? 
  • UK Regulations & Planning Permissions
  • Septic Tank Q&A
    • Can you have a septic tank without a leach field? 
    • Does shower water go into a septic tank? 
    • How long does a septic tank last? 
    • How much does it cost to have a septic tank replaced? 
    • How often should a septic tank be emptied? 
    • Can I empty my own septic tank? 

How Much Is A Septic Tank? (including labour cost)

As you might expect, new or replacement septic tank installation costs can be high depending on where you live, the type of ground you have nearby and many other factors.  

The average cost to buy a septic tank ranges from £800 for a small one to £1500 for a large one. The cost to install ranges from about £2000 to £4000. 

On average, the total quote you may receive may be anywhere from £2500 to £3500 in total.

Comparing Quotes Could Save up to 33%:

=> Looking for a custom house floor plan? Click here to fill out our form, a member of our team will be in touch.

→ Click To Get Quotes

Factors To Consider For The Job

Septic Tank Installation

  • Replacement or new septic tank. You’ll find a difference in septic tank replacement costs compared to a new installation as much of the infrastructure will already be there. 
  • Pipework. Replacement tanks will already have the connecting pipework from the house, whereas new ones will need the added expense of purchase and installation. 
  • Foundations.  New installations will need concrete foundations for the tank, while replacement tanks won’t. 
  • Disposing of soil. When you dig out the holes needed for tank and soakaway, you’ll produce a lot of soil. Yes, some of this will be used up with back-fill, but there will be a lot of leftovers, and you’ll have to put it somewhere.  
  • Empty tank. If you’re replacing an old tank, you’ll need to empty all the sludge that’s built up over time before you can move it. You’ll also have to rinse it out until it’s safe enough to remove it to the waste disposal site.  
  • What type of subsoil.  The underlying geology of your subsoil will govern how easily the tank can drain. Clay will be extremely difficult and you might have to install additional drainage. 
  • Type of contractor. A specialist contractor may take on the entire job and supply the tank too. A local building contractor may call in specialist subcontractors. 
  • Project duration. This depends on the type of ground and whether the tank needs new foundations and plumbing. Durations range from 3 days to 7 days.

Comparing Quotes Could Save up to 33%:

→ Click To Get Quotes

Purchasing 

Factors involved with the purchase costs include: 

  • Size of tank. Both the size and construction material will vary the purchase cost. 
  • Type of retailer. You’ll have a choice of specialist supplier or building supplies merchant, both of which will have their own range of prices. 

Remember when asking for quotations that most contractors won’t add VAT to their final figures unless you ask.  

Another thing to remember is that prices will vary depending on where you live. London and the South East of England will be more expensive than anywhere else. 

How Do Septic Tanks Work? 

There are two distinct ways to use a septic tank.  With a soakaway and without.  

As from 1st January 2020, it is now illegal to use a septic tank that discharges directly into a surface waterway, without using a soakaway. We, therefore, won’t consider this type. We’ll talk in more detail about this in the next section when we deal with the regulations. 

Septic tank with a soakaway  

Older tanks were made from brick or concrete. Most modern ones can be made from fibreglass or polyethene.  

A septic tank settles and retains the fine solids inside the tank until levels rise enough for the tank to be emptied. Depending on the amount discharged from the house, this can take months or years. 

Bacteria digest the dirty water while in the tank, and as it seeps out into the soakaway or drainage field natural bacteria found in the ground continue the treatment.  For this to work correctly, the septic tank must have a thriving bacteria population and the surrounding subsoil must be free draining. 

Over time, the bacteria in the subsoil creates biomass which can interfere with the drainage. At this time, the effluent will leach to the surface or back up along the pipework to the house. 

The household needs to use biodegradable cleaning materials. Regular cleaning materials such as bleach, detergents and other similar products interfere with bacterial growth and the settlement of solids within the tank and in the drainage field.

Comparing Quotes Could Save up to 33%:

→ Click To Get Quotes

UK Regulations & Planning Permissions

On 1st January 2020 new rules came come into force regarding septic tanks discharging to surface water.  Now, installations cannot discharge directly into a surface watercourse. All septic tank discharges have to drain into a drainage field (also called an infiltration system) or must connect to some other small sewage treatment plant. 

To install a new septic tank you must have planning permission and comply with the UK Building Regulations as well as hold a permit. If you are replacing an existing tank, you usually don’t need planning permission. If in doubt, contact your local authority for advice. 

When dealing with sewage and wastewater disposal, it’s important to use suitably qualified contractors to ensure they follow the various regulations. One of the trade associations, British Water has a list of accredited wastewater treatment plant technicians who will install and maintain your septic tank or other types of the sewage treatment plant in line with current regulations.

Comparing Quotes Could Save up to 33%:

→ Click To Get Quotes

Septic Tank Q&A

Can you have a septic tank without a leach field? 

From 1st January 2020, all septic tanks must drain through a leach field and not directly into a surface watercourse. There are two alternatives to this arrangement. 

  • Connect to a mains drainage system. 
  • Connect to another type of sewage treatment plant. 

Does shower water go into a septic tank? 

All wastewater from inside the house must be diverted to a septic tank. This includes water from toilets, sinks, showers, baths, washing machines etc. However, rainwater runoff from roof guttering does not have to be treated. In fact, it’s better if it isn’t, otherwise, the bacterial balance will be affected and the tank will be filled to overflowing faster than the water can soak away. 

How long does a septic tank last? 

This answer depends on the material from which the septic tank is made.  A steel one will last for up to 15 to 20 years due to the problems with rust. Plastic and fibreglass tanks last about 30 years, while concrete tanks can last for more than 40 years. 

How much does it cost to have a septic tank replaced? 

This depends on the material, where you live in the country and any other work that needs to be done on installation. Average total purchase and installation costs vary from about £2800 to £4500. Remember, there might be more costs depending on whether the infrastructure needs to be upgraded. 

How often should a septic tank be emptied? 

This depends on how much the tank holds and how many people live in your house. On average it’s a good idea to empty it about once a year. If you live on your own, you may get away with once every two years. 

Can I empty my own septic tank? 

If you are a registered waste haulier, then possibly yes. Otherwise, no you can’t.  

In the UK, only registered and certified carriers who comply with the Environment Agency’s regulations may carry hazardous waste. Sewage falls into this classification. Not only do you need special equipment, but you also have to have certified vehicles and a place authorised to receive your sludge.

Comparing Quotes Could Save up to 33%:

→ Click To Get Quotes

Primary Sidebar

Pages

  • 15 Disadvantages Of Fibreglass Roofing (Here’s What To Know!)
  • 15 North East Facing Gardens Pros & Cons (Ultimate Guide)
  • 16 Disadvantages Of Karndean Flooring: Is It Worth It? (UK Guide)
  • 17 Problems With Acer Trees: UK Edition (What To Do)
  • 45+ False Chimney Breast Ideas: Best Living Area Examples
  • 8 Problems With Amtico Flooring (Read This Before Buying!)
  • 9 Most Common Faults Of Karcher Pressure Washers (How To Fix Them)
  • Aqualisa Shower Problems (Solutions Explained UK)
  • Are Soda Crystals The Same As Bicarbonate Of Soda? (3 Differences + Uses)
  • Artex Removal (Ultimate Guide UK)
  • Average Deep House Cleaning Costs (2025 Price Guide UK)
  • Back Boiler Removal Costs: The Ultimate Guide (2025)
  • Baking Soda vs Bicarbonate of Soda (Definitive Guide)
  • Bathroom Fitting Cost: 2025 Installation & Renovation Prices UK
  • Bathtub Installation Costs & Fitting Prices: 2025 Guide
  • Block Paving Cost: 2025 Driveway Paving Prices (per m2) UK
  • Brick Summer House Cost: How To Save In 2025
  • Can You Mount A TV Above A Log Burner? (UK)
  • Can You Paint Matt Over Silk? (UK Paint Guide)
  • Can You Put Zoflora In Washing Machine? (No! Do This Instead)
  • Can You Use Baking Powder For Cleaning? (Yes! Here’s How)
  • Can You Use Emulsion As Undercoat? (The Definitive Guide)
  • Can You Use Kitchen Paint In A Bathroom? (Answer Explained)
  • Can You Use Masonry Paint On Wood? [3 Application Tips]
  • Can You Use Polyfilla On Wood? (The Definitive Guide)
  • Carpet Fitting Cost 2025: Installation & Laying Prices UK
  • Chimney Breast Removal Cost 2025: Compare Prices UK
  • Clothes Not Smelling Fresh After Tumble Drying (Why & Fixes)
  • Complete Bathroom Tiling Cost Guide (2025 Prices)
  • Complete Cobblestone Driveway Costs (Prices Per m2)
  • Complete Velux Loft Conversion Cost Guide UK (2025)
  • Concrete Driveway Cost UK: 2025 Imprinted & Stamped Prices
  • Conservatory Prices: Compare 2025 Installation Costs UK
  • Cost Of Extension Over Garage: Save Money In 2025 (UK)
  • Cost of Laying a Patio: 2025 Price Calculator UK (m2)
  • Cost of Rewiring a House: 2025 UK Price Comparison
  • Cost Of Running Electricity To Shed: Save In 2025
  • Cost of Velux Windows: 2025 Fitting & Installation UK
  • Cost To Lower Your Ceiling In 2025: Money Saving Tips
  • Demolition Cost per M2 (Garage/House): 2025 Prices UK
  • Disadvantages Of Corian Worktops In The UK (11 Cons)
  • Do Wickes Have a Cutting Service? (Answer Explained)
  • Does Vinegar Bleach Clothes? (9 Ways To Use Vinegar In Laundry)
  • Does Washing Machine Use Hot Water? Not Always (Here’s Why)
  • Double Glazing Cost 2025: Window Installation Prices UK 
  • Electrician Call Out Fees & Price List: 2025 Cost & Charges UK
  • Enzymatic Cleaners (Everything You Need To Know)
  • Fuse Box Replacement Cost: Complete 2025 Price Guide UK
  • Garage Conversion To Bedroom Cost Guide: Save Money In 2025
  • Garage Door Repair Costs: How Much In 2025? (UK Prices)
  • Garage Gym Conversion: Costs, Process & Tips (2025)
  • Garage Roof Replacement Costs: 2025 Price Guide UK (per M2)
  • Garden Clearance Costs In 2025: How To Save Money (UK)
  • Garden Room Extension Costs: 2025 Price (Savings Guide)
  • Garden Room With Bathroom Costs & Price Guide (2025)
  • Gardener Prices 2025: The Ultimate Cost Guide
  • Government Home Improvement Loans UK: Ultimate Guide (2025)
  • Granite Worktop Installation Costs: Save In 2025 (UK Guide)
  • Gravel Driveway Cost UK: 2025 Prices For All Types (per m2)
  • Gutter Cleaning Prices List 2025: UK Cost Comparison
  • House Extension Cost 2025: Compare Building Prices UK
  • House Rendering Cost: 2025 Exterior Walls Guide (m2) UK
  • How Long Does Gloss Take To Dry? The Definitive Guide
  • How Much Does A Washing Machine Weigh? (In KG)
  • How Much Does It Cost To Move Radiators? Definitive Guide
  • How Much Electricity Does A Washing Machine Use? (Washer Energy Consumption Explained)
  • How Much Postcrete Per Post? (5 Key Factors UK)
  • How Much Salt For The Dishwasher? (A Guide To Optimal Usage)
  • How Much To Build A Garage: 2025 Costs UK (Single & Double)
  • How To Clean A Very Stained Toilet Bowl: 14 Ways (UK Guide)
  • How To Disconnect A Gas Cooker (5 Steps)
  • How To Disguise Drain Covers In Gardens: UK (11 Ways)
  • How To Fill Gap Between Oven and Countertop: 5 Fixes
  • How To Fill Holes In Plasterboard: UK Guide (3 Methods)
  • How To Get Biro Off Leather: 13 Ways (UK Guide)
  • How To Hide Cooker Hood Ducting (DIY Guide UK)
  • How To Remove Airlock From Gravity Fed System: 5 Steps
  • How To Remove Limescale From Toilets Below The Waterline (UK Guide)
  • How To Scare Away Pigeons But Not Other Birds: UK (15 Ways)
  • How To Stop Ivy Growing Through Fence: UK Guide (13 Ways)
  • How To Stop Salt Coming Out Of The Wall: 2-Step Fix (UK)
  • How To Wash Sofa Covers Without Shrinking (Step-by-Step Guide)
  • Is Teflon Banned In UK? [Answer Explained]
  • Karndean Flooring Cost 2025: UK Installation & Fitting Prices (per m2)
  • Kitchen Fitting Cost 2025: New Installation Prices UK
  • Kitchen Sink Installation Cost: 2025 Replacement Prices UK
  • Loft Conversion Cost 2025: Attic & Dormer Prices UK
  • Loft Insulation Cost: 2025 Price Comparison UK (per m2)
  • Mist Coat Ratio: What’s The Perfect Mix? (Do This!)
  • Mounting TV On Chimney Breast (Yes Or No?)
  • New Driveway Cost: 2025 Installation Prices (m2) UK
  • Oil-Filled Radiators: 2025 Running Cost (UK Guide)
  • Outside Tap Fitting Costs: Installation Prices In 2025
  • Painting & Decorating Costs 2025: Room Prices & Day Rates UK
  • Painting A Breeze Block Wall: 5 Steps & Tips
  • Parquet Flooring Cost: 2025 Fitting & Installation Prices UK 
  • PAT Testing Cost 2025: Appliance Certification Prices UK
  • Patio Door Glass Replacement Costs: How To Save In 2025 (UK)
  • Patio Doors Cost: 2025 Sliding & uPVC Installation Prices UK
  • Plastering Cost 2025: House & Walls Skimming Prices (m2) UK 
  • Plumber Hourly Rates: 2025 Costs & Pricing Guide UK
  • Porch Extension Costs Guide (2025 Prices)
  • Postcrete Vs. Concrete: UK Comparison Guide
  • Removing Emulsion Paint From Plaster Walls: 5-Step Guide UK
  • Resin Driveway Cost UK: 2025 Installation Prices (Per M2)
  • Roof Replacement Cost: 2025 New Installation Prices UK
  • RSJ Steel Beam Costs: Installation Prices (2025)
  • Rules For Communal Gardens In Flats: UK Guide (11 Rules)
  • Save On Amtico Flooring Costs: How Much In 2025? (UK Guide)
  • Save On Drain Unblocking Costs (2025 Price Guide)
  • Save On Excavation Costs: UK Pricing In 2025
  • Save On Flat Roof Extension Costs: 2025 Prices Explained
  • Save On Oven Cleaning Prices: 2025 Cost Guide UK
  • Scaffolding Cost 2025: Compare Hire & Rental Prices UK
  • Septic Tank Cost 2025: Replacement & Installation Prices UK
  • Sitemap
  • Standard Desk Height UK: Guide & Tips
  • Stopping Loft Condensation: 10 Things To Do (Fix)
  • Stud Wall Cost: 2025 Partition Installation & Build Price UK
  • Suspended Ceiling Costs Guide: 2025 Pricing Explained (UK)
  • Tapered Or Square Edge Plasterboard? The Definitive Guide
  • Tarmac Driveway Cost: 2025 UK Price Calculator (per m2)
  • The Cost Of Moving A Bathroom Upstairs: 2025 Pricing
  • Toilet Installation Costs In 2025: The Ultimate Guide (UK)
  • Top 13 Most Energy Efficient Washing Machines: UK 2025 Guide
  • Top 20 Plasterboard Alternatives (Choose This!)
  • Top 7 Best Sugar Soap Alternatives (DIY, Natural, Homemade)
  • Total Wallpapering Costs Guide: 2025 Pricing & Quotes (UK)
  • Tree Surgeon Prices 2025: Compare Tree Removal Costs UK
  • Types of Washing Symbols UK: The Ultimate Guide (2025)
  • UK Guide To Waste Pipe Dimensions: Sizes, Applications & Fittings
  • Ultimate Brick Shed Cost Guide (2025 Prices Explained)
  • Ultimate Replumbing House Costs Guide (2025 Pricing UK)
  • Walk In Shower Installation Costs: How Much In 2025? (UK)
  • Washing Machine Compartment Drawers (Ultimate Guide UK)
  • Wet Room Installation Costs: 2025 Fitting Prices UK
  • What Are White Goods? (Answer Explained UK)
  • What Does Hotpoint F05 Error Mean? (Fixes)
  • What Is Baking Soda Called In The UK? (Answered + Common Uses)
  • What Is Rinse And Spin On A Washing Machine Mean? (UK Guide)
  • What Size Drill Bit For Wall Plug? (UK Guide)
  • What’s The Cost Of A Home Sauna? (2025 Price Guide UK)
  • Where Do You Put Vinegar In A Front Load Washer? (UK Guide)
  • Where To Buy Hydrogen Peroxide For Cleaning (UK)
  • Where To Buy Rubbing Alcohol (UK)
  • Where To Put Powder In A Washing Machine? (UK Guide)
  • White Vinegar vs Distilled Malt Vinegar: Your Ultimate Guide
  • Why Does Gloss Go Yellow? 5 Reasons & Fixes (Do This!)
  • Why Is Borax Banned In The UK? [Yes, Here’s Why]
  • Why Is My Bathroom Extractor Fan Not Working? (7 Easy Solutions)
  • Your Kitchen Rewiring Cost Guide: Save Money In 2025
  • Zinc Roofing Costs: Save Money In 2025 (UK Guide)

> TRADESMEN REGISTER HERE<
CONTACT · BLOG · ABOUT · Products · Sitemap · PRIVACY POLICY · TERMS OF USE
Copyright © 2025 HOMEOWNERCOSTS.CO.UK