Schilling played for Shadow Mountain High School in Phoenix, before attending Yavapai College in Prescott, Arizona in 1985.

Schilling began his professional career in the Boston Red Sox farm system as a second-round pick in what would be the final January draft in MLB. He began his professional career with the Elmira Pioneers, then a Red Sox affiliate. After two and a half years in the minor leagues, Schilling and Brady Anderson were traded to the Baltimore Orioles in 1988 for Mike Boddicker. He debuted in the Major League with the Orioles (1988–1990), and then spent one year with the Houston Astros (1991). Schilling was traded to the Philadelphia Phillies, in exchange for Jason Grimsley, on April 2, 1992.

After having struggled with the Orioles and Astros, Schilling was given the chance to pitch and start with the Philadelphia Phillies on a regular basis and flourished as the ace of the Phillies staff, leading the team in wins (14), ERA (2.35), strikeouts (147) and shutouts (4) in his first season with them in 1992. During the Phillies’ pennant run in 1993, Schilling went 16–7 with a 4.02 ERA and 186 strikeouts. Schilling led the Phillies to an upset against the two-time defending National League champion Atlanta Braves in the National League Championship Series. Although he received no decisions during his two appearances in the six-game series, Schilling’s 1.69 ERA and 19 strikeouts (including the first 5 Braves hitters of Game 1, an NLCS record) were enough to earn him the 1993 NLCS Most Valuable Player Award. The Phillies went on to face the defending world champion Toronto Blue Jays in the World Series. After losing Game 1, he pitched brilliantly in his next start. With the Phillies facing elimination the day after losing a bizarre 15–14 contest at home in Veterans Stadium, Schilling pitched a five-hit shutout that the Phillies won, 2–0.

Schilling was named to the NL All-Star team in 1997, 1998, and 1999 and started the 1999 game. In 1997, he finished 14th in NL MVP voting and fourth in NL Cy Young voting. During this season he set the Phillies single-season strikeout record with 319, surpassing the previous record of 310 strikeouts set by Steve Carlton whom had held the record since 1972. Schilling either led or tied for the Phillies leader in wins, complete games, shutouts, and ERA among starters each season from 1997 to 1999, averaging 16 wins per season over those three years despite the team never finishing the season with a winning record. Unhappy with the team’s performance, he requested a trade to a more competitive team in 2000 and was subsequently dealt to the Arizona Diamondbacks. His 101 career victories ranks sixth all-time for Phillies pitchers, 20th in ERA (3.35), 23rd in games appeared in (242), sixth in games started (226), 34th in complete games (61), 13th in shutouts (14), fourth in strikeouts (1554), and eighth in innings pitched (1659.1).

Schilling was traded to the Diamondbacks on July 26, 2000, for first baseman Travis Lee and pitchers Vicente Padilla, Omar Daal, and Nelson Figueroa. With Arizona, he went 22–6 with a 2.98 ERA in 2001, leading the majors in wins and innings pitched. He also went 4–0 with a 1.12 ERA in the playoffs. In the 2001 World Series, the Diamondbacks beat the New York Yankees in seven games. Schilling was 1–0 in that World Series with a 1.69 ERA and 26 strikeouts in 21 innings, though he also allowed a go-ahead home run in the 8th inning of Game Seven. He shared the 2001 World Series MVP Award with teammate Randy Johnson (who relieved Schilling in Game Seven and got the win after the Diamondbacks’ dramatic ninth-inning comeback). Schilling and Johnson also shared Sports Illustrated magazine’s 2001 “Sportsmen of the Year” award. During the World Series Schilling received two other honors, as he was presented that year’s Roberto Clemente and Branch Rickey Awards, the first Arizona Diamondback so honored for either award.

In 2002, he went 23–7 with a 3.23 ERA. He struck out 316 batters while walking 33 in 259.1 innings. On April 7, 2002, Schilling threw a one-hit shutout striking out 17 against the Milwaukee Brewers. Both years he finished second in the Cy Young Award voting to Johnson. Schilling finished the 2003 season with an 8–9 record and a 2.95 ERA in 168 innings while striking out 194 batters. In November 2003, the Diamondbacks traded Schilling to the Boston Red Sox in exchange for Jorge de la Rosa, Casey Fossum, Mike Goss, and Brandon Lyon.

During a game as a Diamondback in 2003, he damaged a QuesTec camera with a bat. According to Schilling, the umpire behind the plate had said “I can’t call that pitch a strike, the machine won’t let me.” This led to a fine and a public exchange of insults with Major League Baseball executive Sandy Alderson who accused Schilling of whining and wanting balls to be called strikes. In response Schilling said Alderson was “ignorant to the facts and ignorant about what I said.”

The trade to Boston reunited Schilling with Terry Francona, his manager during his final four years with the Philadelphia Phillies. On September 16, 2004, Schilling won his 20th game of 2004 for the Red Sox, becoming the fifth Boston pitcher to win 20 or more games in his first season with the team, and the first since Hall of Famer Dennis Eckersley in 1978. Schilling ended his regular season with a 21–6 record.

On October 19, 2004, Schilling won Game 6 of the 2004 American League Championship Series against the New York Yankees. Notably, he won this game playing on an injured ankle—the same injuries that contributed to his disastrous outing in Game 1 of the ALCS. These injuries were so acute that by the end of his Game 6 performance, blood visibly soaked part of his white sock, which is now referred to as “the bloody sock”. The victory forced a Game 7, which the Red Sox would go on to win to capture the pennant and make their first World Series appearance since 1986. Schilling pitched (and won) Game 2 of the 2004 World Series for the Red Sox against the St. Louis Cardinals. In both series, he had to have the tendon in his right ankle stabilized repeatedly, in what has become known as the Schilling tendon procedure, after the tendon sheath was torn during his Game 1 ALDS appearance against the Anaheim Angels. As in Game 6 of the ALCS, Schilling’s sock was soaked with blood from the sutures used in this medical procedure, but he still managed to pitch seven strong innings, giving up one run on four hits and striking out four. This second bloody sock was placed in the Baseball Hall of Fame after Boston’s victory over St. Louis in the World Series. A four-game sweep of the World Series erased the Curse of the Bambino. On February 23, 2013, the first bloody sock was sold at a live auction at the Fletcher-Sinclair Mansion for $92,613 to an anonymous bidder.

Schilling was once again runner-up in Cy Young voting in 2004, this time to Minnesota Twins hurler Johan Santana, who was a unanimous selection, receiving all 28 first-place votes. Schilling received 27 of the 28 second-place votes. Later, the entire Red Sox team was named Sports Illustrated’s 2004 Sportsmen of the Year, making Schilling only the second person to have won or shared that award twice.

Schilling campaigned for President George W. Bush in 2004, while certain members of the ownership of the Red Sox campaigned for the challenger, Senator John Kerry (D). Schilling said he was encouraged to run for Kerry’s seat in the U.S. Senate in 2008 as a Republican. However, Schilling was quoted in The Boston Globe as saying that he intended to pitch in 2008, which would preclude a Senate run.

In interviews in October 2004 and February 2006, Schilling said about Gomez:

Schilling began 2005 on the disabled list due to recurrent ankle injuries. He returned in July as Boston’s closer. He eventually returned to the starting rotation and continued to struggle. The Red Sox made it to the playoffs, but were swept by the Chicago White Sox in three games.

He was called to Capitol Hill to testify about steroid use in March 2005, not as a suspected user but rather as a vocal opponent. He has said that Jose Canseco’s statistics should be thrown out due to his admitted use of steroids, and has also said that unless he can refute allegations that he used performance-enhancing drugs, Roger Clemens should be stripped of the four Cy Young Awards he has won since 1997.

For the 2006 season, Schilling was said to be healthy. He began the season 4–0 with a 1.61 ERA. He finished the year with a 15–7 record and 198 strikeouts, with a respectable 3.97 ERA. On May 27, he earned his 200th career win, the 104th major league pitcher to accomplish the feat. On August 30, Schilling collected his 3,000th strikeout. Schilling has the highest ratio of strikeouts to walks of any pitcher with at least 3,000 strikeouts, and is one of four pitchers to reach the 3,000-K milestone before reaching 1,000 career walks. The other three who accomplished this feat are Fergie Jenkins, Greg Maddux, and former Boston Red Sox ace and teammate Pedro Martínez.

Schilling is a supporter of care for amyotrophic lateral sclerosis (ALS) sufferers. His organization, Curt’s Pitch for ALS, allows fans and organizations to sponsor him, donating to the ALS Association for every strikeout he throws. He also donated to the charity his $25,000 winnings in a celebrity version of Jeopardy! that originally aired on November 9, 2006. In the 2004 playoffs, after the operation on his ankle, Schilling wrote “K ALS” (short for “strike out ALS”) on his shoe, knowing that the cameras would be focusing on his foot numerous times while he was pitching. He also does a weekly radio show with WEEI-FM in Boston that raises over $100,000 each year for ALS patients and research.

Schilling has played EverQuest and EverQuest II and has reviewed two of the game’s many expansion packs for PC Gamer magazine. Schilling has played World of Warcraft and became a regular guest on the World of Warcraft podcast The Instance. In 2006 Schilling created Green Monster Games, which Schilling stated was not named after the Fenway left field wall. In early 2007, the company’s name changed to 38 Studios.

In January 2007, Schilling announced on the Dennis and Callahan show that after talking with his family, he had changed his mind and did not want to retire at the conclusion of the 2007 season. He sought to negotiate an extension to his current contract, but Red Sox executives announced that they would not negotiate with him until after the season citing Schilling’s age and physical condition as factors in their decision. Schilling went on to say he would become a free agent at the end of the season, for the first time in his career, and would not negotiate with the Red Sox during the 15 days after the end of the World Series when the team has exclusive negotiating rights with potential free agents. On a June appearance on the Dennis and Callahan Show, Schilling stated he would accept a one-year extension to his contract at his current salary if the Red Sox offered it to him. Questioned on his statement, Schilling said, “I said I wouldn’t negotiate a deal during the season, and I’m saying that now. But I would accept that offer.”

On June 7, 2007, Schilling came within one out of his first career no-hitter. Schilling gave up a two-out single to Oakland’s Shannon Stewart, who lined a 95-mph fastball to right field for the A’s only hit. Schilling followed up his one-hitter with two poor starts and was sent back to Boston on June 20 for an MRI on his shoulder and was placed on the disabled list. He returned from the disabled list on August 6, pitching at least six innings in each of his nine starts following the All-Star break.

Schilling continued his career postseason success in 2007, throwing seven shutout innings in a 9–1 victory over the Angels in the ALDS, wrapping up a three-game sweep for Boston. However, he did not fare as well pitching in Game 2 of the ALCS against Cleveland, surrendering nine hits—two of them home runs—and five earned runs in just 4⁄3 innings. He did start again in the sixth game of the series, pitching seven complete innings during which he recorded five strikeouts, surrendering no walks with only two earned runs to gain the victory and force a Game 7. He earned his third win of the 2007 playoffs in Game 2 of the 2007 World Series leaving after 5⁄3 innings, striking out four while allowing only four hits. With this win, he became only the second pitcher over the age of 40 to start and win a World Series game (Kenny Rogers became the first just one year prior). As Schilling departed in the 6th inning, fans at Fenway Park gave Schilling a standing ovation.

Schilling filed for free agency on October 30, 2007. He said he would seek a one-year deal, and according to ESPN First Take and his own blog page 38 Pitches. Schilling later signed a one-year deal with the Boston Red Sox for the 2008 season. Schilling missed all of the 2008 season because of a shoulder injury. The injury was first revealed in February 2008 and the treatment options became a point of contention between Schilling and the Red Sox management. On March 13, 2008, the Red Sox placed Schilling on the 60-day disabled list as he continued to rehabilitate his right shoulder. On June 18, 2008, Curt Schilling left the team to be reevaluated after suffering pain when throwing off the mound. On June 20, 2008 Schilling stated on WEEI’s Dennis and Callahan show that he would undergo season-ending surgery and that he had possibly thrown the last pitch of his career. On June 23, 2008, Schilling underwent biceps surgery, during which a small undersurface tear on the rotator cuff was discovered and stitched, and a separation of the labrum was repaired. According to his surgeon, he could begin throwing in four months.

On January 29, 2007, Schilling announced in an interview that he would support Senator John McCain, who became the Republican nominee in the 2008 presidential election. In the same interview, he criticized then-presidential candidate and Senator Hillary Clinton (D) for her comments criticizing the war in Iraq. Schilling also turned up on the campaign trail several times stumping for McCain.

During a radio show appearance on May 8, 2007, Schilling criticized Barry Bonds, stating: “He admitted to cheating on his wife, cheating on his taxes and cheating on the game.” Soon after, Schilling issued an apology on his blog, stating “it was absolutely irresponsible and wrong to say what I did,” without, however, indicating his opinion on the statements’ veracity.

In 2007, Schilling engaged in another war of words with a writer, this time with Boston Globe sports columnist Dan Shaughnessy. Shaughnessy in his column and during television appearances has criticized Schilling for the condition he showed up in for spring training, referred to him as “the Big Blowhard” and mocked Schilling’s blog and radio appearances. Schilling has responded by using the Sons of Sam Horn forum and his own blog to point out errors in Shaughnessy’s columns.

On April 27, 2007, broadcaster Gary Thorne said that he overheard Red Sox catcher Doug Mirabelli say that the blood on the sock used by Schilling in Game 6 of the 2004 ALCS was actually paint. Mirabelli accused Thorne of lying and a day later, after talking to Mirabelli, Thorne backed off his statement saying he misinterpreted what was intended as a joke, “Having talked with him today, there’s no doubt in my mind that’s not what he said, that’s not what he meant. He explained that it was in the context of the sarcasm and the jabbing that goes on in the clubhouse.”

After the 2008 season, Schilling released a blog post blasting former-Red Sox teammate Manny Ramirez’s conduct before Ramirez left the team.

In January 2008, Schilling announced that he would be focusing on an MMORPG project after his retirement. Comic book creator Todd McFarlane and fantasy author R.A. Salvatore were working with Schilling on the project. The new game was developed under the code-name Copernicus. A single-player RPG set in the same setting, titled Kingdoms of Amalur: Reckoning, was released by his company 38 Studios in February 2012. Executives from 38 Studios introduced the game at the Comic-Con 2010 convention in San Diego.

On March 23, 2009, Schilling officially announced his retirement from professional baseball after 20 seasons. Schilling ended his career with a 216–146 record, 3.46 ERA and 3116 strikeouts, 15th-most in MLB history. He was selected to the Boston Red Sox hall of fame in 2012. Having last pitched in 2007, Schilling became eligible for the 2013 Baseball Hall of Fame ballot, but he did not receive sufficient votes for election, receiving 38.8% of the vote. On August 2, 2013, Schilling was inducted into the Philadelphia Phillies Wall of Fame. In 2019 Baseball Hall of Fame balloting, Schilling’s support increased to 60.9%. In 2020 Baseball Hall of Fame balloting, announced on January 21, 2020, Schilling appeared on 70% of the ballots cast, falling five percent short of the 75% election threshold. It was his eighth of a maximum 10 times appearing on the BBWAA ballot.

Schilling was mentioned as a possible candidate for U.S. Senate in the special election in Massachusetts for the seat left vacant by the deceased Senator Ted Kennedy. However, he ruled out a run during his September 24, 2009, appearance on Dennis and Callahan, a popular Boston sports radio talk show. In 2009, Schilling endorsed Scott Brown for the seat. During the campaign, Martha Coakley, the Democratic candidate, referred to Schilling as a Yankee fan. Coakley was ridiculed for the comment; critics said it showed she was out of touch with the Boston community. Schilling joked about the incident: “I’ve been called a lot of things… But never, and I mean never, could anyone ever make the mistake of calling me a Yankee fan. Well, check that, if you didn’t know what the hell is going on in your own state, maybe you could.”

In a Fox News interview on January 18, 2010, Schilling was asked about his own political ambitions. He said that it was not time.

In July 2010, the Rhode Island Board of Economic Development approved a $75 million guaranteed loan to 38 Studios. 38 Studios promised to bring 450 jobs to the state by the end of 2012. In May 2012, 38 Studios defaulted on its loan from the state of Rhode Island and failed to meet payroll obligations to its employees. 38 Studios and its subsidiary, Big Huge Games, then laid off their staffs with a mass email. Some of the laid-off employees may have second mortgages because the company had not actually sold homes for them as part of a relocation package. Some have accused Schilling of hypocrisy based on the conflict between his professed views on “big government” and the studio’s relationship with “big government”. On November 1, 2012, Schilling was sued by the state in connection with the loan. Governor Lincoln Chafee said: “My message to Rhode Islanders is this: I know that you work hard for your paychecks, and for your tax dollars to be squandered is unacceptable. The Board’s legal action was taken to rectify a grave injustice put upon the people of Rhode Island.”

Schilling debuted on ESPN as a baseball color analyst on April 4, 2010, on the pre-game show for the 2010 season opener between the New York Yankees and Boston Red Sox. He has written for WEEI.com, 38pitches.com, and WordPress.com. In 2014, he was named as an analyst for ESPN’s Sunday Night Baseball, although his subsequent cancer diagnosis prevented him from working the telecasts for most of the season. On September 14, 2014, Schilling returned to the Sunday Night Baseball booth as the Yankees played the Baltimore Orioles.

Schilling is one of just 11 players born in the state of Alaska to play Major League Baseball, but considers his family’s native Pittsburgh metro area to be home and is a fan of the Pittsburgh Steelers. He went to high school in Phoenix, Arizona, attending Shadow Mountain High School. Until 2013, Schilling lived in Medfield, Massachusetts, in Drew Bledsoe’s former home. In late 2013, Schilling’s 8,000 square foot home in Massachusetts was put on the market with a listing price of $3 million. Various personal belongings, including a golf cart, were also listed for sale.

On February 5, 2014, Schilling revealed that he had been diagnosed with and was being treated for throat cancer. On June 25 of that year, Schilling announced that the cancer was in remission. Schilling said his cancer was a result of using smokeless tobacco for 30 years. He also used his experiences to warn Madison Bumgarner, who is also a long-time smokeless tobacco user (a ‘dipper’), of the risks of using smokeless tobacco.

In November 2014, Schilling got into a day-long Twitter argument with baseball writer Keith Law over the creation–evolution controversy, where he argued for creationism against Law’s defense of evolution, after which ESPN decided to suspend Law’s Twitter account. ESPN commented that “Keith’s Twitter suspension had absolutely nothing to do with his opinions on the subject”, but it remains unclear what other motivation is behind the act, since the conversation between Schilling and Law reportedly “never really turned hostile”, with many reading the details feeling that his suspension was “ridiculous”. Schilling’s account was not suspended, and he continued to tweet. Returning to Twitter after the ban expired, Law’s first tweet “Eppur si muove” (“And yet it moves”) made clear that Schilling’s complaints about his posts contradicting his argument were in fact the reason for the suspension.

On February 25, 2015, Schilling posted a congratulatory tweet to his then-17-year-old daughter Gabby for her acceptance to college and the school’s softball team. Some responses to his tweet made crude references to rape, fisting and anal sex, among other sexual references. Schilling posted to his blog screen captures of some offending tweets, along with the real identities of the Twitter handles, whose jobs, schools and relatives he claimed to have contacted. At least two of the Twitter users were known to have been punished, with one losing his part-time job as a ticket seller for the Yankees, and still another being suspended from Brookdale Community College. Schilling claimed at least seven others were also penalized by their jobs or athletic teams.

On August 25, 2015, ESPN.com suspended Schilling’s coverage of the ongoing Little League World Series and Sunday Night Baseball after he posted a Twitter meme that compared Muslim Jihadism and German Nazis, “the math is staggering when you get to the true [number]s”. Schilling deleted and apologized for the controversial tweet the same day. Schilling was also suspended from the next Sunday night game, in which Chicago Cubs pitcher Jake Arrieta threw a no-hitter. On September 3, 2015, ESPN announced his suspension would cover all remaining 2015 Sunday Night Baseball games as well as its 2015 MLB playoff coverage.

On April 20, 2016, ESPN announced that they had fired Schilling after he shared an “anti-transgender” Facebook post, saying, “ESPN is an inclusive company. Curt Schilling has been advised that his conduct was unacceptable and his employment with ESPN has been terminated.” Schilling’s social media post came shortly after passage of the North Carolina transgender restroom law. In September 2017, Schilling accused ESPN of a double standard when reporter Jemele Hill was not fired or suspended following a controversial social media post about Donald Trump. In an on-air phone interview with CNN, Schilling defended Hill’s right to speak her mind, then stated, “I wasn’t fired for speaking my mind; I was fired for being a conservative.”

Schilling had announced that he would challenge Senator Elizabeth Warren in the 2018 U.S. Senate election in Massachusetts, but ended up dropping out and supported Shiva Ayyadurai in the race. Schilling has also expressed interest in running for president in 2024 if Donald Trump is re-elected in 2020.