Warmzilla vs Boxt: Boiler Installation Review
Update: August 2026
Although Warmzilla and Boxt have their merits, iHeat* is our recommended new boiler installation provider in August 2026.
We found their fixed price, online quotation system very easy and quick to navigate through, and got the most competitive price out of all the providers we tested.
A good range of boilers were available to select from with warranty and after-care arranged and confirmed by iHeat*.
No hidden costs were added and a financing option to pay monthly was available to apply for, if required.
A next day installation slot was available and the communication was efficient.
To get a wider range of opinions, a high Trustpilot rating indicates most customers had a very positive installation experience. As of August 2026, iHeat are also a Which? Trusted Traders approved service.
Visit iHeat* for a no-obligation and instant online quote.
Warmzilla vs Boxt: Battle of the Boilers
When putting in a new boiler, one of the biggest decisions is which brand to choose. Two of the front runners in the UK boiler market are Warmzilla and Boxt. They both make reliable, energy efficient boilers, but have some differences that set them apart. This article compares the key factors to weigh up when deciding between Warmzilla or Boxt for your next boiler installation.
Boiler Types and Sizing
Warmzilla and Boxt offer similar ranges of boiler types – combination, system and conventional. They also both use digital technology to precisely size the boiler to your home’s needs based on things like house size, insulation and existing radiators. This prevents over or under firing and ensures optimum efficiency.
One difference is that Warmzilla offers more choice if you want an eco-friendly boiler. Their Green range includes hybrid, hydrogen-ready and renewable-compatible models. So if you want a greener boiler, Warmzilla edges ahead.
Warranties and Certifications
When getting a new boiler, guarantees and certifications provide peace of mind. Warmzilla and Boxt both offer lengthy warranties on parts and labour. However Boxt have a edge – they provide a lifetime guarantee on heat exchangers, compared to Warmzilla’s 12 years. So Boxt pips it for long-term boiler cover.
In terms of industry certifications, both brands carry all the important ones like Gas Safe and TrustMark. So you can rest assured you’re getting qualified engineers and high quality products either way.
Smart Controls and Connectivity
The latest trend is smart thermostats that connect to an app on your phone. They enable features like controlling your heating on the go, custom schedules and tracking energy usage.
Warmzilla and Boxt both offer smart controls with their high-end boilers. However Boxt’s own-brand controls get better reviews from customers. Their smart stats are intuitive and the accompanying app is slick and reliable. Warmzilla’s equivalent doesn’t seem to be quite as polished. So when it comes to smart controls, Boxt is the smarter choice.
Installation and Servicing
A key consideration when getting a new bolier is who will install it. The good news is that both Warmzilla and Boxt use only Gas Safe registered engineers who are experts at fitting their respective brands. Installation is smooth and efficient whichever you pick.
Both brands offer UK-wide cover for boiler servicing and repairs. Pricing is broadly similar – service plans start from around £80-100 per year. Warmzilla just clinches it though by offering longer call out times – they provide 24/7 emergency cover compared to Boxt’s standard working hours.
Cost and Buying Process
In terms of upfront costs, Warmzilla boilers start a little cheaper than Comparable Boxt models. However, the pricing structure and discounts Warmzilla show you online can be confusing. Their initial price often doesn’t match what you actually pay. With Boxt, their website pricing is more transparent and matches the final quote.
The process of buying is smooth with both brands – everything can be done online including surveys, quotes, ordering, etc. Boxt just edges things with their slick buying journey that keeps you updated every step of the way via email and text.
Reputation and Reviews
With such large companies, reputation and customer feedback are useful indicators around quality and service. Boxt just pip Warmzilla to the post when it comes to ratings and reviews. They have a Which? Trusted Trader rating of 4.7 out of 5 from over 11,000 reviews, with 82% rating their service as excellent.
Warmzilla still perform strongly though with a Trustpilot rating of 4.4 from over 40,000 reviews. Their service gets praised – any issues seem to get sorted promptly by helpful staff. But a few more customers experience problems versus Boxt.
The Verdict: Your Best Boiler Buy
While both deliver quality boilers, smart controls and professional installation, Boxt just has the edge overall. Their transparent prices, lifetime guarantee, positive reviews and smart connectivity give them the top spot for your next boiler purchase and installation.
However, if you specifically want a greener boiler, Warmzilla’s renewable range provides more eco-friendly options. So weigh up these key factors against your own priorities to decide is if Warmzilla or Boxt will heat your home happily ever after!