Season 20 (2003-2004)
- The five-day limit for returning champions is lifted, meaning players can keep playing as long as they keep winning.
- The opening credits have changed to an orange and blue background, with details of the set visible within it, and the Jeopardy! logo gained a black color scheme. To mark the show's 20th anniversary, a "20th Anniversary" byline is seen in Futura underneath the Jeopardy! logo. There is also an alternate logo with no byline. In either case, there are miniature Jeopardy! logos flying in the background, including one that flies over the main logo at certain points; other times laser beams are flying above and below the logo itself. Finally, the Jeopardy! logo then swings forward to reveal the 2002-2009 set.
- The credits strips are changed from violet folder shaped to blue parallelogram shaped.
- The "DOUBLE" and "FINAL" in Double Jeopardy! and Final Jeopardy!, as well as the Daily Double text, are changed to Impact; the Daily Double text gained a black color scheme to match the season's title card. In later episodes of this season, the "DOUBLE" and "FINAL" in Double Jeopardy! and Final Jeopardy! were changed to red.
- Starting with this season, the contestant introductions were changed to outer box introductions.
- Also, the contestant intro and Final Jeopardy! winnings strips became blue, with black text in a font resembling Helvetica.
- This is the last season where Steven Dorfman is the writer. He died of colon cancer on January 4, 2004 at the age of 48.
- Beginning with this season and continuing until Season 35, the theme music from Rock & Roll Jeopardy! is used during the Teen Tournament, College Championship, and Kids Week. For the next two seasons, it is only used going into and coming out of commercial breaks.
- For at least the last 30 half-hour episodes of Season 20, the display text for video clues and the Final Jeopardy! thinking period is changed back to Korinna, which remains for the next two seasons.
- Also, the clue cards themselves changed from smart quotes and custom apostrophes to straight quotes and plain apostrophes, and the category names temporarily changed from Swiss 911 to Helvetica Condensed.
- Season 20 of Jeopardy! kicks off on September 8, 2003.
- From September 22-26, 2003, Back to School Week is held.
- On the October 15, 2003 episode, Sean Ryan became the show’s first six-day champion and also the first unlimited champion.
- The College Championship aired from November 10-21, 2003 and was held at Yale University.
- The December 18, 2003 episode features Dave Oberhart, one of the show's blind contestants.
- On the January 13, 2004 episode, Tom Walsh becomes the show's first seven-day champion. In addition, the game also ended in a tie resulting co-champions.
- The Teen Tournament airs from February 9-20, 2004.
- The April 21, 2004 episode is dedicated to the memory of Steven Dorfman, who had been a part of the Jeopardy! staff since the first season of the syndicated version.
- From May 3-14, 2004, two weeks of episodes were filmed at DAR Constitution Hall in Washington, D.C. May 3-7 was Kids Week and May 10-14 was Power Players Week which was held for the first time similar to Celebrity Jeopardy!.
- On the June 2, 2004 episode, Ken Jennings makes his Jeopardy! debut.
- On the July 13, 2004 episode, Ken Jennings becomes the first contestant to break $1,000,000 mark in regular gameplay.
- Season 20 of Jeopardy! wraps up on July 23, 2004, and Ken Jennings sets a new one-day record of $75,000.
- Summer repeats air from July 26 to September 3, 2004, with repeats later airing on weekends from September 11, 2004 to September 10, 2005.