Mary Mack will step down as head of Wells Fargo Advisors in order to take on a bigger role in overseeing the company's Community Banking unit which has 94,000 employees, according to a spokeswoman.

A hunt for a replacement for Mack, 53, is already underway, the spokeswoman says.

Mack is replacing Carrie Tolstedt as head of Community Banking at Wells Fargo. Tolstedt, who helped the company build its retail branch network to 6,000 locations in 39 states, is retiring after 27 years at the San Francisco-based company. The Community Banking unit serves more than 20 million retail checking households and 3 million small business owners, according to the company.

As head of the brokerage unit for the past two-and-a-half years, Mack has overseen about 15,000 advisers managing $1.4 trillion in client assets. Like its chief competitors, the wirehouse has been increasingly encouraging its financial advisers to help cross sell other banking products, such as mortgages and securities-based loans.

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William Boland, a senior analyst at research firm Aite Group, says that may have helped her land her new position. “She is very highly regarded, and has been a standard bearer in terms of her willingness to work with the broader bank,” he says.

Boland adds that Wells Fargo has also been known to promote brokerage executives within the company.

“It also fits well with Wells Fargo’s history of rotating executives across different faculties,” he says.

Last year, she oversaw the inking of a deal with Credit Suisse to give Wells Fargo the inside recruiting track on the Swiss bank's U.S.-based advisers, as Credit Suisse had plans to exit the U.S. wealth management market. But of the roughly 250 elite brokers – many multi-million dollar producers – only about 110 joined Wells Fargo.

Many left to join rival firms like UBS.

Mary Mack is stepping down as head of Wells Fargo Advisors in order to oversee the Community Banking unit at Wells Fargo.

Read more: UBS Recruiting Ignites Raiding Claim, Spoils Credit Suisse-Wells Fargo Deal

Brand Meyer, who oversees the Independent Brokerage Group at Wells Fargo Advisers, will serve as interim head of the unit effective July 31, the spokeswoman says.

Mack said in a statement she was excited to join Wells Fargo's Community Banking unit. There are new avenues for growth due to "expanding opportunities to add value to our customers’ lives."

In a statement, CEO John Stumpf praised the "organizational savvy and leadership skills" of Tolstedt and Mack.

In her role leading Wells Fargo Advisors, Mack has been listed among American Banker’s "Most Powerful Women in Finance" for the past two years, moving up to No. 7 last year from No. 24 the year earlier.

Tolstedt has been part the "Most Powerful Women in Banking" ranking since 2003. She was No. 4 in 2015.

Mack joined the firm through its merger with Wachovia, where she had previously served as head of Wealth Brokerage Services.

She is the latest head of a major brokerage firm to depart. Earlier this year, John Taft retired as CEO of RBC Wealth Management-U.S. and Greg Fleming left as president of Morgan Stanley Wealth Management.