The business, which is based in Yorkshire, first started sponsoring the Baggies in 2018 with that deal leading to the creation of now world-famous Boilerman mascot.
The new agreement, which runs to the conclusion of the 2023/24 season, will see the partnership extend to a sixth campaign – making it one of the longest commercial relationships in the club’s history.
Extending their sponsorship with Ideal Heating – formally called Ideal Boilers – is good news for the Baggies at at time when many clubs are looking to get away from having gambling companies as shirt sponsors.
A white paper is due to be published by the Department for Digital, Culture, Media and Sport later this year which could prevent clubs from striking deals with betting companies.
Many fans also feel it in unethical to have a gambling firm on their shirts.
The leading UK manufacturer of combi, system and heat only boilers, Ideal Heating have also provided hundreds of tickets to local organisations, as well as merchandise competitions for Baggies fans.
Simon King, Albion’s chief commercial officer, said: "Ideal Heating are a brand that continues to grow rapidly and are at the forefront of innovation within their sector.
"They are a true partner in every sense of the word and it has been quite a journey with them so far, both on and off the pitch.
“I’m looking forward to seeing our long-standing relationship with Ideal Heating continue to flourish and we will strive to build on the fantastic results our partnership has already delivered.”
Chief executive of Ideal Heating, Shaun Edwards, added: “We take our role as principal sponsor very seriously, but we also like to have a good time – which is why we get on so well with West Brom and its fans.
"Our legendary Boilerman character was born at The Hawthorns three years ago, and is now centre stage in all of our TV ads and installer materials.
“As well as being a part of the team’s success over the past few seasons, we’ve loved getting to know local people, and will continue to focus on our charity and community work throughout this next term.
"We’re incredibly excited to be back for another three years, and look forward to building on everything we’ve already achieved with the club.”