Boiler guide · 5 min read · Updated October 2026
The best combi boilers of 2026: an installer's shortlist
Our shortlist across the ten brands we stock — judged on warranty, value and parts support, not marketing.
How we picked
Three criteria: warranty length with realistic conditions, value for money, and UK parts support. Every model below is one we actually stock or fit — this is a working shortlist, not a sponsorship.
The shortlist
- Best all-rounder — Worcester Bosch Greenstar 4000: 7 years extendable to 10, from £2,635 fitted (30kW)
- Best value long warranty — Ideal Logic Max: 10 years parts and labour at a mid-range price
- Best premium — Worcester Bosch Greenstar 8000+: up to 12 years with conditions
- Best budget with real cover — Baxi 800 Combi 2: 10 years registered, from a 1-year standard — registration matters
- Best for tight spaces — Greenstar CDi Compact: cupboard-sized, up to 10 years with conditions
What we deliberately left out
Any model whose warranty terms we cannot confirm. Where a range's exact cover is unresolved, our shop says so on the product page rather than repeating a marketing number.
The honest caveat
The best boiler is the right size for your home, fitted properly, with a long warranty that is actually registered. A £400 saving on the boiler is wiped out by one out-of-warranty repair. Compare by warranty and total fitted price — our shop shows both.
Common questions
What is the best combi boiler to buy in 2026?
For most homes, the Worcester Bosch Greenstar 4000 balances price, reliability and a warranty extendable to 10 years. On a tighter budget, the Ideal Logic Max's 10-year cover is the best value in our range.
Are expensive combi boilers worth it?
Up to the point where the warranty and build justify it. The premium you want is the one that buys years of cover — not features you will never use.
Ready for a real price?
Build a fitted boiler quote in about two minutes, or browse over 700 supply-only boiler packs in the shop.