Joining on Monday (9 November), Mr Downing will be a member of the Towry board and will take on the role of CFO with immediate effect.
He will succeed Paul Wright, who will remain with the business until his retirement in June 2016.
Mr Downing joins from Legal & General, where he has held a number of senior group positions including group CFO and group merger and acquisition and strategy director.
Prior to joining Legal & General he spent time at Resolution Plc and Britannic Plc.
Rob Devey, chief executive of Towry, said: “We have long demonstrated our commitment to hiring the best talent in the industry and Wadham brings with him significant experience that will support the next phase of our development.
“I would also like to thank Paul for his outstanding contribution to the growth and success of Towry over the last seven years. We are fortunate that we will continue to benefit from his skills and experience over the coming months.”
Mr Downing said: “I am very excited at the prospect of joining Towry at a time of significant change in the financial planning and wealth management industry.
“The business has built a compelling proposition and I look forward to working alongside such a dynamic and well-respected leadership team to help execute the firm’s long-term growth strategy.”