New Boiler: Types & Costs Compared 2026
For most homes a combi boiler is the simplest, best-value new boiler, while larger homes with two-plus bathrooms often suit a system boiler with a cylinder. Heat-only boilers still suit some older setups. Typical fitted prices run £2,000–£4,000 in 2026. Here is how the types compare on cost and suitability, and how to choose.
New boiler types compared
A combi boiler heats water on demand with no cylinder or tank — compact, efficient and ideal for flats and smaller homes with one bathroom. A system boiler works with a hot-water cylinder, so it can serve several taps and showers at once, which suits larger homes with two or more bathrooms. A heat-only (regular) boiler uses a cylinder and a cold-water tank in the loft, and is usually kept where an older traditional system is already in place. The right type depends on your hot-water demand, the number of bathrooms and the existing setup.
New boiler cost 2026
In 2026, a fitted combi swap typically costs £2,000–£3,000, a system boiler £2,500–£3,800, and a heat-only replacement £2,300–£3,500. Switching type — for example system to combi — costs more because tanks come out and pipework is reworked. See our combi boiler prices and new boiler cost guides for detail.
Fuel, brand and efficiency
Most homes run on mains gas; off-grid homes use LPG or oil, and some are weighing a heat pump instead. Across brands, Worcester Bosch, Vaillant, Ideal and Viessmann are the mainstream choices, with premium models offering higher efficiency and longer warranties. A correctly sized, high-efficiency boiler with good controls is what keeps running costs down, so size and controls matter as much as the badge.
How to choose and compare quotes
1. Match the type to your home
Combi for smaller homes, system for two-plus bathrooms, heat-only where a traditional system stays.
2. Size it correctly
Have the output sized on bathrooms and radiator load so it is neither undersized nor wastefully large.
3. Weigh brand, warranty and controls
Balance upfront price against efficiency, warranty length and smart controls that cut running costs.
4. Get three like-for-like quotes
Compare Gas Safe installers on the same boiler, type and scope so you judge value, not just price.
FAQs
Related guides
Get 3 Free Quotes — Gas Safe Installers
BestBuilders matches you with up to 3 vetted Gas Safe heating engineers for a new boiler. Compare quotes — no cost, no obligation.