Plumbing · Updated August 2026
Immersion Heater Replacement Cost UK 2026
Replacing a failed immersion heater element costs £150–£300 fitted. With a new thermostat it runs £200–£400, and on unvented (pressurised) cylinders £250–£450 - the parts are cheap, the draining and access are the labour.
Immersion heater cost by job — 2026
Fitted prices; the element itself is £15–£60 - access, draining and testing are what you are paying for.
| Job | Typical fitted cost | Timescale | Notes |
|---|---|---|---|
| Element replacement (vented cylinder) | £150–£300 | 1–2 hours | The standard job |
| Element + thermostat replacement | £200–£400 | 2 hours | Replace both while it is drained |
| Unvented cylinder immersion | £250–£450 | 2–3 hours | G3-qualified engineer required |
| Thermostat only | £100–£180 | 1 hour | If water is scalding or cutting out |
| Timer / smart control added | +£80–£200 | — | Heat water on cheap-rate hours |
Indicative 2026 UK prices, compiled from published installer pricing (Checkatrade, MyJobQuote, MyBuilder and BookaBuilder cost guides, August 2026). BestBuilders has no quote history in this category yet, so treat these as a budgeting guide and confirm against three written quotes.
What changes the cost
| Cost factor | Typical impact | Why it matters |
|---|---|---|
| Cylinder type | +£100–£150 | Unvented cylinders legally need a G3-qualified engineer, and the safety checks add time |
| Scale and corrosion | ±£50–£100 | A scaled-in element in hard-water areas can fight for an hour before it lets go |
| Access to the boss | ±£50 | A cylinder boxed into an airing cupboard with 5cm clearance is a joinery job first |
| Draining required | ±£40–£80 | Top-entry immersions on some cylinders swap without a full drain-down |
| Element quality | £10–£40 on parts | Incoloy or titanium elements resist scale far longer than the cheapest copper - fit once |
Immersion heater cost by UK region — 2026
Modelled from regional labour rates rather than measured in this category — materials cost much the same everywhere, the labour does not.
| Region | Typical cost | vs UK average |
|---|---|---|
| London | £190–£520 | +25–30% |
| South East | £170–£480 | +15–20% |
| South West | £160–£420 | +5% |
| Midlands | £150–£400 | baseline |
| North England | £140–£380 | −5–10% |
| Scotland | £140–£360 | −10% |
| Wales | £140–£360 | −10% |
| Northern Ireland | £130–£340 | −15% |
Getting it priced properly
1. Check the thermostat first
Cold water is sometimes just a tripped or failed stat - £100–£180 rather than a full element job. Any plumber checks this first.
2. Match the engineer to the cylinder
Vented copper cylinder: any good plumber. Unvented sealed cylinder: G3-qualified, no exceptions - it is a pressure vessel.
3. Fit the scale-resistant element
In hard-water Britain the £30 Incoloy element outlives the £15 copper one several times over. Cheapest part, biggest lifespan difference.
What this costs at a glance
The same table, drawn.
Immersion heaters — frequently asked questions
£150–£300 fitted on a standard vented cylinder in 2026, £200–£400 with a new thermostat, and £250–£450 on unvented cylinders where a G3-qualified engineer is required.
Usually the element has scaled up and burned out, or the thermostat has failed or tripped. The reset button on the stat is worth pressing before you call anyone.
Five to fifteen years depending on water hardness and element quality. In hard-water areas a scale-resistant Incoloy or titanium element makes the difference.
On a vented cylinder a competent DIYer with an immersion spanner can - but it combines mains electricity, stored hot water and draining. On unvented cylinders it must legally be a G3-qualified engineer.
Related cost guides
Full cylinder replacements priced.
Combi, system and heat-only swaps priced.
Full refits priced by size and spec.
Reviewed by the BestBuilders editorial team on 18 August 2026 · Next scheduled review: November 2026 · See our editorial standards.