The office provides wealth management services and the eight-strong team will still be led by financial planning directors Shaun Davison and Spencer Bennett.
The financial terms of the acquisition were not disclosed.
Looking to hire
Paul Stansfield, Cowgills managing partner, said: “We have over 180 employees based across the north and are actively recruiting the best people to join our growing team.
“Investing in the Ilkley office is an important part of our growth strategy and we will be supporting Shaun and Spencer as they continue to grow the business and service their clients.”
Cowgills, which was established in 1983, has a turnover of over £13m ($17.2m, €15.2m) and has seen a 65% growth in business in the last five years.