Time Warner Cable announced that chairman and CEO Glenn Britt will retire at the end of 2013, with Rob Marcus, currently president and COO, stepping in to take over the top job.

The CEO changeover will take effect Jan. 1, 2014, the company said. Britt, 64, will remain on the operator’s board in a non-executive role.

During Britt’s tenure, the cable biz has changed dramatically — expanding from just standalone cable TV to encompass broadband, voice and commercial services, while its video customer base has steadily declined. Time Warner Cable, the second-biggest U.S. MSO, has been the target of merger overtures by Charter Communications and Liberty Media chairman John Malone, who believes operators need to achieve greater scale.

Tensions between pay TV distributors and programmers also have increased in recent years, as content costs have soared. TW Cable is currently locked in a standoff over retransmission fees with CBS, whose stations may go dark next week if the companies can’t agree on a deal.

Marcus (pictured above), 48, also was elected to TW Cable’s board of directors effective immediately. He joined the cable company in 2005 and was named CFO in 2008, working with Britt and during the cable company’s 2009 spinoff from Time Warner Inc.

Previously, Marcus held various positions at Time Warner Inc., including senior VP of mergers and acquisitions, and prior to that was an attorney with Paul, Weiss, Rifkind, Wharton & Garrison, where Time Warner Inc. was his client.

Marcus “has the vision, financial prowess, operating acumen and unrelenting drive that make him the ideal CEO,” N.J. Nicholas Jr., lead director of Time Warner Cable’s board, said in a prepared statement. “The board is also very pleased that Glenn will remain chairman and CEO through 2013 as part of our thoughtful and seamless transition process.”

Britt, who began his career at Time Inc. in 1972 and served stints at HBO, was named TWC topper in 2001. He had been reported to plan to retire this year.

“I have had the privilege of being in this industry for more than 40 years and witnessing first-hand the most momentous evolution in communications technology ever experienced — we have truly been at the forefront of changing the way the world communicates,” Britt said in a statement.