Electric Boiler vs Gas Boiler Cost Calculator

How this calculator works

This calculator works in ranges rather than single figures, because real quotes, yields and tariffs genuinely vary that much. It starts from typical UK price, output and savings ranges drawn from published 2026 industry guides and official scheme documentation, then scales them by the quantities you enter and adjusts them for each choice you make below. The result is a low-to-high band that a realistic outcome is likely to fall within, not a promise of the figure you will achieve.

An electric boiler costs to installed against to for gas in 2026, a broadly even contest upfront, but running a typical home electrically costs roughly to a year against to on gas, a gap of around annually that no installation saving survives. The arithmetic is simply the fuel prices: electricity at 24.7 to 26.1 pence per kWh against gas around 6 pence, with both boiler types converting fuel to heat at similar efficiency.

Home size

Home size scales the installation estimates: larger homes need higher output units, bigger cylinders where fitted and sometimes more pipework, while flats and small houses sit below the three bedroom baseline that published guide prices describe. It does not scale the running cost figures, which follow the demand number you enter instead.

Annual heat demand (kWh)

This is the heat your home needs over a year for space heating and hot water. A typical UK three bedroom house needs roughly 10,000 to 14,000 kWh; if you heat with gas today, your annual gas kWh from your bill multiplied by about 0.85 for boiler efficiency is a good estimate. Every running cost figure on this page scales directly with this number.

Where you live

Heating labour is not priced uniformly across the UK, with published guides putting London and South East installation quotes roughly 15 to 25 percent above the national average. The hardware costs the same everywhere, so the difference sits in engineer day rates, access and parking.

Electricity tariff

An electric boiler on the standard cap pays 24.7 to 26.1 pence per kWh, but a system designed around storage, a well insulated cylinder charged in cheap overnight windows on an Economy 7 or smart tariff, cuts the effective rate by a third or more. The gas figure uses standard cap gas rates throughout, so this option shows how far tariff engineering can close the gap; the honest answer is meaningfully, but never fully.

What else affects the figures

Electric boilers therefore win only where gas is unavailable or unwelcome: flats without flue options, off-grid homes, listed buildings, and low-usage properties where the running gap barely accrues, and even there the modern comparison is the heat pump, which delivers gas-free heating at roughly a third of the electric boiler’s running cost and carries the Boiler Upgrade Scheme grant that electric boilers do not. Gas carries costs its unit rate hides, a standing charge around to a year, annual servicing and eventual policy risk on fossil heating, but none of it closes a annual gap. The pragmatic 2026 summary: gas where you have it, heat pump where you are leaving it, and the electric boiler as the niche solution for homes that can host neither.

Certification, planning and grid connection

Electric boilers and heaters need no Gas Safe engineer, but the electrical work is regulated in its own right: new circuits and consumer unit work fall under Part P of the Building Regulations and belong to a qualified electrician who can self-certify through a competent person scheme. High-output electric boilers need supply capacity checking before purchase, occasionally involving the network operator, and any storage-based strategy relies on tariff choice, so confirming Economy 7 or smart tariff availability with your supplier is part of the design rather than an afterthought. Electric heating carries no flue, no condensate and no annual gas safety requirements, one of its genuine conveniences.