Bregman began playing tee-ball at age 4. In his first game, he turned an unassisted triple play by catching a line drive, tagging a runner, and then stepping on second base. He was a batboy for the University of New Mexico baseball team, and in 2004 served as a batboy for a game against Arizona State University and his then-favorite baseball player, Dustin Pedroia. His best friend is Blake Swihart, who played for the Arizona Diamondbacks. Bregman and Swihart played travel ball together growing up.

In 2009, Bregman led his high school team to a state championship as a freshman shortstop. He batted leadoff, hitting for an average of .514 with three home runs, including one during the championship game that left Isotopes Park, the Dodgers’ Class AAA team park. At the October 2010 COPABE Pan American Baseball Championships in Lagos de Mareno, Mexico, while he was a sophomore, he batted .564 for the gold-medal-winning 16-and-under USA National Team, and was named the MVP. That year, at the age of 16, he became the first high school player to win the USA Baseball Richard W. “Dick” Case Player of the Year Award.

On September 8, Bregman became the youngest Astro ever to hit 30 home runs in a season, at 24 years old. On September 12 he picked up his 50th double of the season as well as his 100th RBI and 100th run scored. Bregman became the first Astro to log 100 RBIs in a season since Carlos Lee in 2009, and the first primary third baseman in Major League history to record 50 doubles and 30 home runs in a season. He also became the first player since Albert Pujols in 2012 to hit 30 home runs and 50 doubles, and drive in 100 runs. Bregman also extended his on-base streak to 39 games (the longest in team history since 1999), and tied Jeff Bagwell’s franchise record of reaching base in 51 consecutive games on the road (established in 2001).

In 2011, he batted .678 as a junior in high school, and established a season record in New Mexico with 19 home runs. Bregman was named first team All-State, and received All-Metro and All-District honors. In the fall of that year he led the 18-and-under U.S. National Team to a gold medal at the International Baseball Federation World Championships.

In 2013, he batted .369/.417/.546 with 104 hits (second in the nation), 18 doubles (third in the SEC), seven triples, six homers, 52 RBIs, 59 runs, and 16 steals in 17 attempts, and had a 23-game hitting streak. Bregman won the 2013 Brooks Wallace Award as the country’s best college shortstop. He was also voted first-team All-American by Baseball America, the American Baseball Coaches Association (ABCA), Perfect Game, and the Jewish Sports Review. In addition, he was named the 2013 National Freshman of the Year by Baseball America, Collegiate Baseball, and the National Collegiate Baseball Writers Association (NCBWA), and was voted 2013 SEC Freshman of the Year and first-team all-SEC by the league coaches. Moreover, he was named 2013 ABCA First-Team All-South Region, National Collegiate Athletic Association (NCAA) Baton Rouge Regional Most Outstanding Player, Louisiana Freshman of the Year, and SEC Player of the Week (March 25, 2013), and named to the 2013 USA Collegiate National Team (for which he batted .361).

He was one of four finalists for the 2015 Golden Spikes Award, presented annually to the nation’s top college player and won by outfielder Andrew Benintendi. Also, he was a candidate once more for the Brooks Wallace Shortstop of the Year Award that he had won in 2013.

In 2014, he batted .316/.397/.455 with 16 doubles, 6 home runs, 35 runs, and 12 stolen bases. Bregman was voted 2014 second-team all-SEC, NCAA Regional All-Tournament Team, SEC All-Tournament Team, Second-Team All-Louisiana, and named to the 2014 USA Collegiate National Team. He shared an apartment that season with teammate and future fellow major league All Star Aaron Nola.

In 2015, Bregman batted .312/.406/.534 with 22 doubles (tops in the SEC), 9 home runs, 49 RBIs, 37 stolen bases (leading the SEC, and the second-most steals in a season in LSU history), and 206 assists (leading the conference), led the nation’s No. 1-ranked baseball team to the College World Series, and won LSU’s Skip Bertman Award, which goes to the player who best exemplifies the spirit of the LSU Baseball program. He was also voted the Rawlings Gold Glove winner at shortstop by the ABCA, and voted first-team All-American by both Baseball America and the NCBWA for the second time, First Team D1Baseball, First Team Perfect Game, and Second Team Collegiate Baseball.

Bregman signed with the Astros in June 2015 for a $5.9 million signing bonus. He made his professional debut with the Quad Cities River Bandits of the Class A Midwest League in late June. In late July, the Astros promoted Bregman to the Lancaster JetHawks of the Class A-Advanced California League. Playing shortstop for the two teams, he batted an aggregate .294/.366/.415.

Bregman started 2016 with the AA Corpus Christi Hooks in the Texas League, hitting .297 with 14 home runs and a .975 OPS, was named the league’s Player of the Week on April 17, and was named a AA mid-season All-Star. In AAA with the Fresno Grizzlies, in 18 games he hit .333/.373/.641/1.015. Between the two teams, in 80 games he hit .306/.406/.580 with 20 home runs and 61 RBIs, while playing 64 games at shortstop and 13 at third base.

On July 25, 2016, the Astros purchased Bregman’s contract from the Grizzlies, adding him to their 25-man roster. He made his major league debut at third base against the New York Yankees that same day. He was the first position player from the 2015 Draft to debut in the Major Leagues. After he was hitless in his first 17 major league at bats through five games, the Astros moved him up to second in the batting order, to get him better pitches and demonstrate their confidence in him.

For the 2017 season, he batted .284/.352/.475 with 39 doubles and five triples (the latter two both ninth in the AL), 19 home runs, 88 runs, 71 RBIs, and 17 stolen bases (tied for the lead among all major league third basemen). His .331 batting average against left-handers was 9th in the AL. Bregman played third base primarily (132 games), and led AL third basemen in fielding percentage (.970; the 4th-highest fielding percentage by a third baseman in team history), while also playing 30 games at shortstop. Houston won the AL West division with a 101–61 record, thus advancing Bregman to his first career major league playoff.

In 2018 the Astros renewed Bregman’s contract at $599,000 – an increase of $60,000. In June he was named AL Player of the Month, after batting .306/.372/.713 in 108 at bats, with 11 home runs and 30 RBIs (a new Astros record for June). He became the second Astros third baseman to win the award, along with Art Howe (May 1981). Bregman was also named the AL Player of the Week for the week of June 25 – July 1, during which he batted .464/.516/1.179 in 28 at bats with five doubles, five home runs, and ten RBIs.

Batting .284 with 17 home runs, 57 RBIs, and 29 doubles, he was named to the 2018 MLB All-Star Game. Bregman was also selected to participate in the 2018 Home Run Derby. After he hit a go-ahead home run in the 10th inning off of Ross Stripling, he was named the Astros’ first All-Star Game MVP.

For the 2018 regular season, he batted .286/.394 (4th in the AL)/.532 (6th in the AL) with 31 home runs and 51 doubles (leading the AL; the 3rd-most in Astros history), 83 extra base hits (2nd in the league), 96 walks (3rd), 105 runs and 103 RBIs (each 5th in the AL), 7.0 at bats per strikeout (9th), and a 15.1 power–speed number (10th). Bregman batted .386/.488/.735 with runners in scoring position, the highest slugging percentage in the major leagues and the second-best OPS (behind Mike Trout). He demonstrated plate discipline, as he was 2nd in the American League in lowest swinging strike percentage (4.3%) and O-Swing percentage (20.0%), and 3rd in contact percentage (88.5%), and 3rd in the major leagues in walks/strikeout (1.13).

In the 2018 American League Division Series Bregman batted .556, and his .714 OBP was the third-highest all-time in a division series, while his 1.333 slugging percentage was fourth-highest all-time.

For the 2019 regular season, he batted .296/.423/.592 (tied for 8th-highest in Astros history), led the major leagues in walks (119; 6th-most in Astros history) and walk-to-strikeout ratio (1.43), and led the American League in times on base (292; 9th-highest in team history) and Wins Above Replacement (“WAR”; 8.4; second-best in Astros history). Bregman was also 2nd in the AL in on base percentage (.423), 3rd in home runs (41; 7th-most in team history), slugging percentage (.592), and on base plus slugging percentage (1.015), 4th in runs scored (122; 9th-most in Astros history), 5th in RBIs (112), extra base hits (80; 8th-most in Astros history), and sacrifice flies (8), 7th in games played (156), 8th in at-bats-per-strikeout (6.7), and 9th in at-bats-per-home-run (13.5; 10th-best in team history). He swung at the lowest percentage of pitches outside the strike zone of all major league batters (18.8%). He was one of three major league players with at least 100 runs, 100 walks, and 100 RBIs, joining Mike Trout and Juan Soto. He became the only player in Astros history to hit 40 or more homers in a season while striking out fewer than 100 times, and joined Joe Morgan as the only players in team history to amass 100 or more walks and strike out fewer than 90 times in a season. On defense, he played 99 games at third base, and 65 games at shortstop.

In the 2019 postseason, Bregman enjoyed an excellent ALDS against the Tampa Bay Rays, batting .353/.450/.647 with two doubles, one home run, three walks, and two RBIs. Bregman’s bat went ice cold in the ALCS and first three games of the World Series, though, as he struggled through a 4-for-31 (.129) slump with only one home run and three RBIs. Bregman broke out of his slump in Game 4 of the World Series by hitting 3-for-5 with a grand slam and 5 RBIs in an 8-1 Astros win that tied the series at 2-2. The Astros eventually lost the series in seven games.

In late 2019, the Houston Astros sign stealing scandal broke, revealing that the Astros had illegally stolen signs using technology in 2017 and 2018. MLB investigated and eventually released its report while punishing the Astros organization. In January 2020, Bregman appeared before the media at the Astros’ annual fan festival in Houston that week. He answered repeated attempts by reporters to have him address the scandal with variations of the same phrase: “The commissioner made his report, made his decision, and the Astros made their decision and I have no further comment on it.” On February 13, the Astros held a news conference at their spring training facility to address the scandal. Bregman said, “I am really sorry about the choices that were made by my team, by the organization, and by me. I have learned from this and I hope to regain the trust of baseball fans.” At that same news conference, Astros owner Jim Crane denied allegations that Bregman and other Astros players wore buzzer devices in 2019, saying, “I truly believe there were no buzzers, ever, and I don’t even know where that came from.”

On July 27, 2020, Bregman hit his 100th career home run off of Kendall Graveman of the Seattle Mariners.

In January 2020, Bregman became engaged to Reagan Howard in Colorado.