The WTA Tour Championships is a tennis tournament played annually at the end of the season for the top-ranked players on the Women's Tennis Association (WTA) tour. The event's current sponsored name is the Sony Ericsson Championships.

The championships were held for the first time in August 1971 in Houston, Texas as one of a series of tournaments sponsored by Virginia Slims. This event, however, was staged before the end of the series. In 1972, the tournament was moved to Boca Raton, Florida (USA) as a climax event at the end of the series. From 1972 to 1974, the event was held in October, before switching to March from 1975 until 1986. The WTA then decided to adopt a January-to-November playing season, and so the event was switched to being held at the end of each year. As a consequence, there were two championships held in 1986. The event was held in Los Angeles, California from 1974 to 1976 before moving to Madison Square Garden (MSG) in New York City in 1977. With the exception of a one-year move to Oakland, California in 1978, the Championships remained at MSG until 2000. The event then briefly moved to Munich, Germany in 2001. More recently, it moved back to Los Angeles, California from 2002 to 2005. The 2006 and 2007 editions were held in Madrid, Spain. Doha, Qatar will host the 2008, 2009, and 2010 editions before passing the flag to Istanbul, Turkey, which is expected to host the 2011, 2012, and 2013 events.

From 1971-1978, the event was known as the Virginia Slims Championships. When Avon took over as the tour sponsor from 1979-1982, the event was known as the Avon Championships. Virginia Slims returned as the tour sponsor in 1983 and the event name reverted to the Virginia Slims Championships. It remained that way until 1994 when Virginia Slims ended their sponsorship of the WTA Tour. In 1995, without a tour sponsor, the event was simply referred to as the WTA Tour Championships. Since then, the tournament has been named after other event sponsors. From 1996 to 2000, it was called the Chase Championships. In 2001, it was the Sanex Championships while in 2002, it was the Home Depot Championships. In 2003 and 2004, the event name was once again the WTA Tour Championships. Since 2005, with Sony Ericsson taking over as tour sponsor, the event has been called the Sony Ericsson Championships.

From 1984-1998, the final of the championships was a best-of-five-set match - making it the only tournament on the women's tour to have a best-of-five-set match at any round of the competition. In 1999, the final reverted to being a best-of-three-set match, as had been the case from 1971-1983.

The WTA Tour Championships are generally considered to be the fifth most prestigious event on the women's tour after the four Grand Slam tournaments.