Federer says he might give the honor to someone else.
The 17-time Grand Slam champion was the Swiss flag-bearer at two other Summer Games.
Speaking Monday a day after winning his record-tying seventh Wimbledon title, Federer says an announcement on the flag choice could come "in the next 10 days or so."
The opening ceremonies are July 27. The Olympic tennis competition, which is being held at the All England Club, starts the following day.