After 20 years in charge of Lawrence’s largest bank, Chuck Warner is retiring.

Warner, president for U.S. Bank in Lawrence, plans to end his banking career Dec. 31, two decades after starting work as trust manager for First National Bank of Lawrence, in the same downtown building at 900 Mass.

“You work all your life so you can do what you want,” Warner said Monday, in his corner office. “And when you can do what you want without having to work, why work?

“I don’t have to be a banker. I know a lot of people who are what they do, but I’ve done other things in my life, and I’m looking forward to a new chapter.”

While Warner, who will turn 62 next month, started his banking work at First National Bank of Lawrence, he has been president of each of its successors: Mercantile Bank, then Firstar Bank, and now U.S. Bank, with 80 employees in Lawrence handling $218 million in deposits, according to the latest figures from the FDIC. In Lawrence, only Capitol Federal Savings – a savings and loan – is larger, with deposits of $374 million.

While Warner has been president, banks have taken advantage of deregulation to branch into an array of financial services, while online banking has emerged and a seemingly endless number of competitors have come into the Lawrence market, drawn by the community’s steady long-term growth and future earnings potential.

“It’s been quite a ride,” he said.

Warner hasn’t always been a banker. After earning a law degree from Kansas University in 1970, he went to work as business manager for Centron Films, a Lawrence-based company that produced industrial and educational films. He worked there for 18 years.

Throughout his business career, he’s found time to serve. He was a Lawrence-Douglas County planning commissioner in the late 1970s, when commissioners approved the Plan ’95 comprehensive plan. He’s been on the board of directors for the Lawrence Chamber of Commerce and continues to serve as a board member for Cottonwood Foundation, Douglas County Development Inc. and United Way of Douglas County.

He and his wife, Karen, are co-chairs of the current United Way campaign, an effort to generate $1.7 million in donations and pledges to assist area social-service agencies.

“I’ve got family and friends and travel, and I’m involved in the community,” Warner said. “I’ll keep very busy.”