Billings, who joined Wynn Resorts as its finance chief in 2017, most recently served as the head of Wynn Interactive, the company's 72%-owned unit housing its U.S. online sports betting and gaming business.

Billings will also become a board member.

Maddox took the helm at Wynn in February 2018 after founder Steve Wynn resigned in the wake of sexual misconduct allegations.

"This has not been an easy decision. I am leaving a company that I love and that's full of people I admire," Maddox said.

"But I believe now is the right time for me and for the business."

(Reporting by Sanjana Shivdas in Bengaluru; Editing by Devika Syamnath)