The Philadelphia Phillies are a Major League Baseball team based in Philadelphia, Pennsylvania, in the United States. The Phillies are a member of the Eastern Division of Major League Baseball's National League. From 2004 to the present, the Phillies have played their home games at Citizens Bank Park in the South Philadelphia section of the city. The organization is tied with the San Francisco Giants as the fifth-oldest team in Major League Baseball.

The Phillies have won one World Series Championship in their history, defeating the Kansas City Royals in 1980. Due in part to the age of the club, the Phillies became the first team in the four major American sports to surpass 10,000 losses in franchise history in 2007. The Phillies are known for their loyal and passionate fan base, and are also a league leader in environmental protection.

After being founded in 1883 as the "Quakers," the team changed its name to the "Philadelphias", after the convention of the times. This was soon shortened to "Phillies." "Quakers" continued to be used interchangeably with "Phillies" until 1890, when the team officially became known as the "Phillies." Though the Phillies moved into a permanent home at Baker Bowl in 1887, they did not win their first pennant until nearly 20 years later, after the likes of standout players Billy Hamilton, Sam Thompson, and Ed Delahanty had departed. Player defections to the newly-formed American League, especially to the cross-town Athletics, would cost the team dearly over the next several years. A bright spot came in 1915, when the Phillies won their first pennant, thanks to the pitching of Grover Cleveland Alexander and the batting prowess of Gavvy Cravath, who set the major-league single-season record for home runs with 24. Poor fiscal management after this World Series appearance, however, doomed the Phillies to sink back into relative obscurity; from 1918 to 1948 they only had one winning season. Though Chuck Klein won the MVP in 1932 and the National League Triple Crown in 1933, the team continued to flounder at the bottom of the standings for years.

After lumber baron William B. Cox purchased the team in 1943, the Phillies began a rapid rise to prominence in the National League, as the team rose out of the standings cellar for the first time in five years. The fans responded with an increase in attendance, but it soon became clear that not all was right in Cox' front office. Eventually, it was revealed by Cox that he had been betting on the Phillies, and he was banned from baseball. The new owner, Bob Carpenter, Jr., tried to polish the team's image by unofficially changing the name to the "Blue Jays"; however, the new moniker did not take, and it was quietly dropped by 1949. Instead, Carpenter turned his attention to the minor league affiliates, devoting significant resources to the farm system for the first time in the history of the franchise. By the 1950s, the Phillies had gone from cellar-dwellers to pennant contenders thanks to the "Whiz Kids," led by a lineup of young players developed by the Phillies' farm system that included future Hall of Famers Richie Ashburn and Robin Roberts. Their 1950 season was highlighted by the last day, pennant-clinching home run by Dick Sisler to lead the Phillies over the Dodgers and into the World Series. The Phillies' popularity drove the Athletics to leave the city for Kansas City and, eventually, Oakland.

As the Phillies sank back to mediocrity, a bright spot began to develop after the departures of the "Whiz Kids." The team seemed destined to make it to the World Series after strong showings in the early part of the decade; alas, it was not to be. The Phillies squandered a six-and-a-half game lead with a ten-game losing streak to close the 1964 season, and lost the pennant by one game to the St. Louis Cardinals. The "Phold of '64" is one of the most notable collapses in sports history. The Phillies moved out of Connie Mack Stadium and into Veterans Stadium, and their new maroon uniforms, at the end of the decade. While some members of the team had admirable performances during the 1970s, the Phillies still clung to their spot at the bottom of the National League table. Ten years after the Phold, they suffered another minor collapse over August and September of 1974, missing out on the playoffs yet again. However, the futility would not last much longer. After a run of three straight division titles from 1976 to 1978, the Phillies won the NL East in 1980 behind pitcher Steve Carlton, outfielder Greg Luzinski, and infielders Mike Schmidt, Larry Bowa, and Pete Rose. In a memorable NLCS, with four of the five games needing extra innings, they fell behind 2–1 but battled back to squeeze past Houston on a tenth-inning game-winning hit by center fielder Garry Maddox, and the city celebrated its first pennant in 30 years.

Facing Kansas City in the 1980 World Series, the Phillies won their first and only world championship in six games, thanks to the timely hitting of Mike Schmidt and Pete Rose. Schmidt, who was the National League MVP for the 1980 season, also won the World Series MVP finals award on the strength of his 8-for-21 hitting (.381 average), including game-winning hits in Game 2 and the clinching Game 6. Thus, the Phillies became the last of the 16 teams that made up the major leagues from 1901 to 1961 to win a World Series. The Phillies made the playoffs twice more after their Series win, in 1981 and 1983, where they lost to the Baltimore Orioles in the World Series, but they would find their near-misses followed by a rapid drop back into the doldrums of the National League basement. The 1992 season would end with the Phillies at the bottom of the barrel, at last place in the National League East. However, their fortunes were about to change.

The 1993 Phillies started the season hot, going 17–5 in April and powering their way to a 97–65 season. The Phillies beat the Atlanta Braves in the 1993 National League Championship Series, four games to two, to earn the fifth pennant in franchise history, only to suffer defeat by the defending world champion Toronto Blue Jays in the 1993 World Series. Toronto's Joe Carter hit a walk-off home run in Game 6 to clinch another Phillies loss. The players' strike in 1994 was a blow to the Phillies' attendance and on-field success, as was the arrival of the Atlanta Braves in the division due to league realignment. Several stars came through Philadelphia, though few would stay, and the minor league system continued to develop its young prospects, who would soon rise to Phillies fame.

In 2001, the Phillies had their first winning season in eight years under new manager Larry Bowa, and would not dip their season record below .500 again from the 2003 season onward. In 2004, the Phillies moved to their new home across the street from the Vet, Citizens Bank Park. Charlie Manuel took over the reins of the clubs from Bowa in 2005, and general manager Ed Wade was replaced by Pat Gillick. Gillick reshaped the club as his own, sending stars away in trades and allowing the Phillies' young core to develop. Though the franchise lost its 10,000th game in 2007, that same core of young players, including infielders Chase Utley, Ryan Howard, and Jimmy Rollins, and pitcher Cole Hamels, responded by winning the East pennant the same season; however, they lost to the Colorado Rockies in the Division Series.

The current team colors, uniform, and logo date to 1992. The main team colors are red and white, with blue serving as a prominent accent. The team name is written in red with a blue star serving as the dot over the "i"s, and blue piping is often found in Phillies branded apparel and materials. The team's home uniform is white with red pinstripes, lettering and numbering. The road uniform is traditional grey with red lettering/numbering. Both bear a script-lettered "Phillies" logo, with the aforementioned star dotting the "i"s across the chest, and the player name and number on the back. Hats are red with a single stylized "P". The script "Phillies" and the red trim are similar to the style worn by the team during 1950 to 1969.

During the 2008 season, the Phillies wear an alternate, cream-colored uniform during home day games in tribute to their 125th anniversary. The uniforms are similar to those worn from 1946 through 1949, featuring no pinstripes and red lettering bordered with blue piping. The accompanying cap is blue with a red bill and a red stylized "P." The uniforms were announced on November 29, 2007, where Phillies shortstop Jimmy Rollins, pitcher Cole Hamels and Hall of Famer Robin Roberts modeled the new uniforms. The Phillies are one of six teams in Major League Baseball that do not display the name of their city, state or region on their road jerseys, joining the Baltimore Orioles, Los Angeles Angels of Anaheim, Milwaukee Brewers, St. Louis Cardinals, and the Tampa Bay Rays.

The Phillies pioneered the use of the batting practice jersey in 1977, wearing a maroon v-necked top with the "Phillies" script name across the chest, as well as the player name and number on the back and a player number on the left sleeve, all in white. Currently, during spring training, the Phillies wear solid red practice jerseys with pinstriped pants for Grapefruit League home games, and solid blue batting practice jerseys with gray pants for away games.

From 1970 to 1991, the Phillies sported colors, uniforms, and a logo that were noticeably different from what had come before, or since, but that were widely embraced by even traditionally minded fans. A dark burgundy was adopted as the main team color, with a classic pinstripe style for home uniforms. Blue was almost entirely dropped as part of the team's official color scheme, except in one area; a pale blue (as opposed to traditional grey) was used as the base-color for away game uniforms. Yet the most important aspect of the 1970 uniform change was the adoption of one of the more distinctive logos in sports; a Phillies "P" that, thanks to its unique shape and "baseball stitched" center swirl, remains instantly recognizable and admired, long after its regular use has ended. It was while wearing this uniform style and color motif that the club achieved its most enduring success, including a World Series title in 1980 and another World Series appearance in 1983. Its continued popularity with fans is evident, as even today Phillies home games can contain many fans sporting caps, shirts, and/or jackets emblazoned with the iconic "P" and burgundy color scheme.

For one game in 1979, the Phillies front office modified the uniform into an all-burgundy version with white trimmings, to be worn for Saturday games. They were called "Saturday Night Specials". The immediate reaction of the media, fans, and players alike was negative, with many describing the despised uniforms as pajama-like. As such, the idea was hastily abandoned.

Another uniform controversy arose in 1994 when the Phillies introduced blue caps on Opening Day which were to be worn for home day games only. The caps were unpopular with the players, who considered them bad luck after two losses. The caps were dumped after being used on the field for a month.

Phillies fans have earned a reputation over the years for their generally rowdy behavior. In the 1960s, radio announcers for visiting teams would frequently report on the numerous fights breaking out in Connie Mack Stadium. Immediately after the final game at the old park, many fans ran onto the field or dislodged parts of the ballpark to take home with them. Later, at Veterans Stadium, the notorious 700 Level gained a reputation for its "hostile taunting, fighting, public urination and general strangeness.

Some memorable incidents include racially-charged discrimination against the Phillies' first African-American player, infielder Richie Allen. Los Angeles Dodgers' pitcher Burt Hooton's poor performance during Game 3 of the 1977 National League Championship Series has often been attributed to the crowd's taunting. In addition, J.D. Drew, the Phillies' No. 1 overall draft pick in 1997, never signed with the Phillies following a contract dispute with the team. Instead, he re-entered the draft the next year and was drafted by the St. Louis Cardinals. Phillies fans were angered over this disrespect and threw batteries at Drew. Many sports writers have noted the passionate presence of Phillies fans, including Allen Barra, who wrote that the biggest roar he ever heard from Philadelphia fans was in 1980 when Tug McGraw, in the victory parade after the World Series, told New York fans they could "take this championship and shove it."

To attract more fans, the Phillies' franchise has used promotions. Two prominent examples are the Hot Pants Patrol, a group of young ladies designed to attract male customers to the ballpark, and the Phillie Phanatic, who has been called "baseball's best mascot. "In Phillies fan culture, it is also not unusual to replace an "f" with a "ph" in words, such as the Phillie Phanatic, or the "Phold" of '64.

The Philadelphia Phillies are the first Major League Baseball team to join the Environmental Protection Agency's Green Power Partnership Program which motivates organizations across the world to purchase green power in order to minimize environmental impact. The Phillies announced on April 30, 2008 that their home field, Citizens Bank Park, will be powered with 20 million kilowatt-hours (kWh) or green energy purchased in Green-e Energy Certified Renewable Certificates (RECs). The EPA stated that this purchase holds the record in professional sports for the largest purchase of 100% renewable energy. The Phillies are among the top three purchasers of green power in Philadelphia, and the executive director of the Center for Resource Solutions, Arthur O'Donnell, wants, "other clubs to take their lead." Aramark Corporation is the Phillies' food and beverage provider at Citizens Bank Park and they are taking major actions in improving the environmental impact of the Phillies' stadium. Glass, cardboard, and plastics used during game day are going to be recycled. Frying oil will be recycled to produce bio-diesel fuel, and biodegradable, recyclable, and compostable products, serviceware, and plastics have been introduced.