Westinsure Webb is based in Truro has been serving clients in the region for over 60 years.
Henry Clayton will remain as CEO of Westinsure Webb until the integration has completed.
Westinsure Webb has two advisers and a total of £70m of assets under advice.
Kelsall Steele Investment Services was established in 1997 and is headquartered in Truro in Cornwall. It was among the earliest of IWP’s acquisitions and has been established as one of the group’s regional hubs.
Henry Clayton, CEO of Westinsure Webb, said: “Our business has been providing advice and excellent service to clients for a period in excess of 60 years. We have always believed in putting our clients first, and that is why Kelsall Steele Investment Services and the personalised and regionalised approach of IWP was the natural fit for us.
"As part of IWP we are also excited to access the opportunity both with the brand and its central support and resources, these will enable us to grow whilst keeping our focus on our clients.”
Wes Nixon, CEO of Kelsall Steele Investment Services, said: “We are thrilled to welcome Westinsure Webb to Kelsall Steele Investment Services and the wider IWP group. This acquisition marks the first step in our growth plans to build IWP’s South West hub into a £500m true Financial Planning business. Henry has built an excellent business and I am looking forward to driving the next phase of growth for our combined businesses.”