1,000L bunded tank supply and install: £2,000–£2,800
1,500L bunded tank supply and install: £2,500–£3,500
2,500L bunded tank supply and install: £3,000–£4,500
Old tank removal adds £250–£600 depending on size and access.
What's included in the cost?
A full oil tank replacement typically includes:
- Supply of the new bunded plastic tank
- Delivery of the tank to your property
- Installation on a prepared base
- Connection to existing pipework
- Safety check and sign off
It typically does not include:
- Base preparation (a new concrete or paving slab base if none exists: add £200–£500)
- Removal and disposal of the old tank (add £250–£600)
- Transfer of remaining oil from the old tank (a specialist pump out service if needed: add £80–£150)
- New pipework if the routing changes
- Building regulations approval if required
Cost by tank type and size
| Tank size | Tank only (supply) | Installed (inc labour) | With old tank removal |
|---|---|---|---|
| 500L bunded | £800–£1,100 | £1,500–£2,200 | £1,800–£2,800 |
| 1,000L bunded | £1,100–£1,500 | £2,000–£2,800 | £2,400–£3,500 |
| 1,500L bunded | £1,400–£1,900 | £2,500–£3,500 | £3,000–£4,200 |
| 2,500L bunded | £1,600–£2,200 | £3,000–£4,500 | £3,500–£5,500 |
Prices inc 20% VAT. Regional variation is significant: London and South East typically 20–30% higher than the North. Always get at least two quotes.
When does a tank need replacing?
Plastic polyethylene tanks (the most common type installed since the 1990s) typically last 20–30 years with proper maintenance. The main signs that replacement is becoming urgent:
- Visible cracking or crazing on the tank surface: plastic degrades with UV exposure over time
- Discolouration: significant yellowing or browning suggests UV degradation
- Leaks or seeps: any oil seeping from the tank body (not a fitting) means immediate replacement
- Tank age over 20 years: inspection recommended; consider replacement if any other symptoms present
- Single-skin tank: new regulations in most cases require bunded tanks; if you're replacing pipework or the boiler, it's a good time to upgrade the tank too
- Failed OFTEC inspection, if a registered technician identifies the tank as non compliant or unsafe
A leaking oil tank can contaminate soil and groundwater. Clean-up costs for a significant spill can reach £10,000–£50,000+, and under environmental law you can be held liable even if the leak was accidental. Home insurance often covers sudden accidental spills but not gradual leaks from a deteriorated tank. Act quickly if you see any signs of leakage.
Steel vs plastic tanks
The vast majority of new domestic installations use polyethylene (plastic) bunded tanks. They are lighter, cheaper, easier to install, and resistant to corrosion. Steel tanks are occasionally used for very large agricultural installations or where fire resistance is required.
If you have an old steel tank, replacement with a modern plastic bunded tank is almost always the right choice. Old steel tanks corrode from the inside out. Internal corrosion products can contaminate your fuel and block boiler filters, and an externally clean tank may have significant internal degradation that's invisible without inspection.
How to choose an installer
Oil tank installation should be carried out by an OFTEC registered technician (Oil Firing Technical Association). OFTEC registration ensures the technician is trained and qualified to work on oil fuel systems and comply with building regulations. An OFTEC registered installer can self certify the work under Part J of the building regulations, which is required for new installations in most circumstances.
To find a registered installer: visit oftec.org and use their technician finder, or ask your heating oil supplier. Most maintain a list of local recommended installers.
Does replacing a tank add home value?
A new, compliant bunded tank doesn't directly add market value, but a failed or non compliant tank can be a deal breaker in property sales. Surveyors regularly flag old single skin tanks or tanks with visible deterioration, and buyers sometimes require replacement as a condition of sale. If you're planning to sell within the next few years and your tank is ageing, proactive replacement removes a potential obstacle.
A new tank is the perfect time to reassess your supplier. See who's cheapest in your area today.
Grant help for tank replacement?
There is no specific grant for oil tank replacement, but if the replacement is being carried out as part of a broader insulation or heating improvement project, some costs may be eligible under ECO4 or similar schemes. See our heating oil grants guide for full details of available support.