BOXT vs iHeat: Online Boiler Installers Compared (July 2026)

Quick answer: BOXT and iHeat both sell fixed-price boiler installation online. BOXT’s advertised prices start from £1,790 installed, iHeat’s from around £1,985 (its entry Glow-worm model, checked July 2026), and both held “Excellent” Trustpilot ratings of around 4.8/5 — BOXT from roughly 56,000 reviews, iHeat from around 10,000.

BOXT is the biggest of the UK’s online boiler installers; iHeat is a smaller, fast-growing rival with a very similar proposition: answer a few questions, get a fixed price in about a minute, and have a new boiler fitted as soon as the next working day. Below we compare the two purely on their published data. For the wider market picture, see our guide to new boiler costs in 2026.

A note on independence: Home Energy Quotes has no commercial relationship with BOXT or iHeat. We have not tested either service ourselves — everything below comes from the companies’ published prices and terms and from Trustpilot, checked in July 2026.

BOXT vs iHeat at a glance

Sources: BOXT published prices, iHeat published prices, Trustpilot (BOXT, iHeat) · checked July 2026.

Pricing compared

BOXT’s headline “from” price of £1,790 installed was the lower of the two when we checked in July 2026, against iHeat’s entry price of around £1,985 for a Glow-worm model. iHeat does not publish a full per-model price list — its online quote tool returns your exact figure — but its indicative fitted prices run from around £1,985 on entry brands such as Glow-worm and Alpha, to roughly £2,100–£3,000 for mainstream models such as Ideal, Vaillant and Worcester Bosch, and higher for premium units. On BOXT, independent price tracking puts a comparable mid-range Worcester Bosch combi at roughly £2,000–£2,600.

As always with fixed-price online quotes, these figures assume a like-for-like swap of a modern condensing boiler in an accessible spot. Changing boiler type or location adds cost with either firm — our boiler types guide explains the differences. Both platforms also state that the price you see online is the price you pay, provided the information you entered was accurate, so answer the questionnaires carefully and photograph the existing boiler and flue if asked.

Brands and warranties

iHeat lists the slightly wider shelf: Worcester Bosch, Vaillant, Viessmann, Ideal, Alpha and Glow-worm — six brands to BOXT’s five (Worcester Bosch, Vaillant, Ideal, Baxi and Navien). Only iHeat carries Viessmann and Alpha; only BOXT carries Baxi and Navien.

On warranties, both top out at 10 years. BOXT’s published manufacturer cover runs up to 10 years on Worcester Bosch and Navien, 7 years on Ideal and Baxi, and 5 years on Vaillant. iHeat lists 10-year warranties on several models, including the Alpha E-Tec NX, Worcester Bosch Greenstar 4000 and Vaillant ecoFIT Pure, with 5–7 years on entry models (all checked July 2026). Every manufacturer warranty is conditional on an annual service, and lengths vary by exact model — verify at checkout. Our best boiler brands 2026 guide compares the manufacturers behind these packages.

Reviews and track record

Both companies held a 4.8/5 “Excellent” Trustpilot rating in July 2026. The obvious difference is scale: BOXT’s roughly 56,000 reviews dwarf iHeat’s roughly 10,000. A larger review base makes a score more statistically robust, but it reflects company size, not necessarily better workmanship — iHeat’s smaller sample is still substantial. Ratings change daily, so check the live BOXT and iHeat pages, and read the recent one-star reviews on both — they tell you more about how problems get resolved than the averages do.

Which one fits your situation?

• Lowest headline price: BOXT’s entry price was around £195 lower when checked in July 2026 — but always compare like-for-like models for your own postcode.
• Brand choice: want a Viessmann or Alpha? Only iHeat lists them. Want Baxi or Navien? Only BOXT does.
• Finance: both advertise finance; iHeat promotes 0% interest-free credit and buy-now-pay-later terms prominently.
• Complex installations: neither online model is ideal for conversions or relocations — an in-person survey may serve you better.

Whichever route you take, size the boiler to the property rather than simply matching the old one — our boiler guide covers sizing and efficiency, and the calculator models what an efficient replacement could save in your region.

FAQs

Is iHeat as trustworthy as BOXT with fewer reviews?

Review volume mostly reflects company size. Both firms held the same 4.8/5 “Excellent” rating in July 2026, and roughly 10,000 reviews is still a large sample. Check each firm’s most recent reviews for current service levels before ordering.

Do BOXT and iHeat really install the next day?

Both advertise next-working-day installation — iHeat specifies ordering before 3pm. In practice availability depends on engineer coverage in your postcode, so treat next-day as best-case rather than guaranteed.

What is included in the fixed price?

Typically the boiler, installation by a Gas Safe registered engineer, flue, system flush or cleanse, a magnetic filter and warranty registration. Extras such as smart thermostats vary by package, so read the line items in each quote before comparing totals.