Boncaster, a subsidiary of Cox Insurance, this week landed a multi-million pound outsourcing deal to administer Jardine Lloyd Thompson's personal lines policyholders.

The five-year contract, for an undisclosed sum, applies to all JLT's personal lines business including its affinity customers.

JLT corporate risks managing director Adrian Gerling said: “Tens of thousands” of policyholders will be affected by the switch, which takes place on October 1.

Gerling refused to comment on the size of the book, but industry sources claim the broker generates around £2m to £3m in commission income from the sector.

“There are three points I want to make about this arrangement,” Gerling said. “First, there will be no redundancies; second we have not sold the business – it is a five-year outsourcing deal; and third we want to grow this account and as such have retained our sales and marketing function.”

One of the factors behind the move is thought to be JLT's takeover of large regional broker Burke Ford in April this year.

An industry source close to the JLT/Boncaster deal said: “JLT had a lot of personal lines business because of the Burke Ford takeover and I think they are taking a strategic approach.”

Gerling added: “We will continue to trade as JLT but this gives us enhanced technology. This gives us the ability to sell something in a different way to our new and existing clients.”

Boncaster sales and marketing director Nick Potts said his company was restructuring its panel of insurers to incorporate JLT's partner insurers at more competitive rates.

Potts said: “We already administer a lot of business of a similar type and we believe we can offer an enhanced service to their customers.”