List of major league baseball progressive single - season home run leaders - wikipedia List of major league baseball progressive single - season home run leaders The Major League Baseball single - season record for the number of home runs hit by a batter has changed many times over the years. Contents 1 Single - season records 2 Progression 3 Home runs per game 4 See also 5 References 6 External links Single - season records Batter Team Age Year HR Reign Record breaker George Hall Philadelphia Athletics 27 1876 5 3 years -- Charley Jones Boston Red Caps 29 1879 9 4 years 6th on July 31 off George Bradley Harry Stovey Philadelphia Athletics 27 1883 14 1 year 10th on August 1 off Jack Neagle Ned Williamson Chicago White Stockings 27 1884 27 35 years 15th on July 9 off Ed Bagley Babe Ruth Boston Red Sox 24 1919 29 1 year 28th on September 24 off Bob Shawkey Babe Ruth New York Yankees 25 1920 54 1 year 30th on July 19 off Dickie Kerr Babe Ruth New York Yankees 26 1921 59 6 years 55th on September 15 off Bill Bayne Babe Ruth New York Yankees 32 1927 60 34 years 60th on September 30 off Tom Zachary Roger Maris New York Yankees 27 1961 61 37 years 61st on October 1 off Tracy Stallard Mark McGwire St. Louis Cardinals 35 1998 70 3 years 62nd on September 8 off Steve Trachsel Barry Bonds San Francisco Giants 36 73 17 years 71st on October 5 off Chan Ho Park Sammy Sosa hit his 66th home run on September 25, 1998, breaking McGwire 's then standing record of 65 home runs. McGwire tied that record less than an hour later and then hit two home runs on each of the next two days to achieve his 70 home run record. Progression Summarized from The Baseball Encyclopedia for older information, and from various news stories for newer information : Four baseball bats that were used in setting single - season home run records. From left to right : bat used by Babe Ruth to hit his 60th home run during the 1927 season, bat used by Roger Maris to hit his 61st home run during the 1961 season, bat used by Mark McGwire to hit his 70th home run during the 1998 season, and the bat used by Sammy Sosa for his 66th home run during the same season. 5, by George Hall, Philadelphia Athletics ( NL ), 1876 ( 70 game schedule ) 9, by Charley Jones, Boston Red Stockings ( NL ), 1879 ( 84 game schedule ) 14, by Harry Stovey, Philadelphia Athletics ( AA ), 1883 ( 98 game schedule ) 27, by Ned Williamson, Chicago White Stockings ( NL ), 1884 ( 112 game schedule ) Williamson benefited from a very short outfield fence in his home ballpark, Lakeshore Park. During the park 's previous years, balls hit over the fence in that park were ground - rule doubles, but in 1884 ( its final year ) they were credited as home runs. Williamson led the pace, but several of his Chicago teammates also topped the 20 HR mark that season. Of Williamson 's total, 25 were hit at home, and only 2 on the road. Noticing the fluke involved, fans of the early 20th century were more impressed with Buck Freeman 's total of 25 home runs in 1899 or Gavvy Cravath 's 1915 total of 24. 29, by Babe Ruth, Boston Red Sox ( AL ), 1919 ( 140 game schedule ) Even with that relatively small quantity, and still pitching part - time, Ruth alone hit more home runs than did 10 of the 15 other major league clubs. The second - highest individual total was 12, by Gavvy Cravath of the Philadelphia Phillies. Ruth homered in every park in the league, the first time anyone had achieved that distinction. Ruth was a pitcher by trade, and the ultimate exception to the axiom that pitchers ca n't hit. Ruth had led the league with 11 in 1918, despite playing only 95 games, and still in the `` dead - ball '' era. By 1919, after the War, the materials for baseballs began to improve and became naturally `` livelier ''. 54, Babe Ruth, New York Yankees ( AL ), 1920 ( 154 game schedule ) Ruth hit just a few more home runs on the road ( 26 ) than he had the previous year ( 20 ), but he hit far more ( 29 ) in the Polo Grounds in New York ( where the Yankees played at the time ) than he had in Fenway Park ( 9 ) in Boston the year before, as he took full advantage of the nearby right field wall, although he also hit many long drives at the Polo Grounds. Of the other 15 major league clubs, only the Philadelphia Phillies exceeded Ruth 's single - handed total, hitting 64 in their bandbox ballpark Baker Bowl. The second - highest individual total was the St. Louis Browns ' George Sisler 's 19. Ruth 's major - league record slugging percentage ( total bases / at bats ) of. 847 stood for the next 80 years. 59, by Ruth, New York ( AL ), 1921 ( 154 game schedule ) Ruth 's slugging percentage was just. 001 less than his record - setting average the previous year. 60, by Ruth, New York ( AL ), 1927 ( 154 game schedule ) Ruth hit more home runs in 1927 than any of the other seven American League teams. His closest rival was his teammate Lou Gehrig, who hit 47 homers that year. 61, by Roger Maris, New York ( AL ), 1961 ( 162 game schedule ) Pushing Maris that year was teammate Mickey Mantle ; slowed by an injury late in the season, Mantle finished with 54. With the season being eight games longer than in previous years, leading to the suggestion that official record keepers place an `` asterisk '' next to the record, many observers derided this situation as a major public relations gaffe by major league baseball. 70, by Mark McGwire, St. Louis Cardinals ( NL ), 1998 ( 162 game schedule ) After an epic battle between McGwire and Ken Griffey, Jr., who both got into the 50s in 1997, many expected the two to take on Maris in 1998. However, the player that competed for the record with McGwire in 1998 was Sammy Sosa of the Chicago Cubs, who propelled himself into the race with a record - setting 20 home runs that June. He would finish with 66 that season and actually led McGwire for approximately 45 minutes after hitting his 66th, until McGwire hit his own 66th, and four more in his final three games of the season. McGwire broke the old records in 144 games -- fewer than even the old 154 game season. That removed season - length as a source of `` asterisk '' controversy, but McGwire 's connection to the steroid scandal introduced a new call for asterisks on this and other records set in this era. On January 11, 2010 McGwire admitted using steroids during the 1998 season. McGwire claimed to use steroids to help heal an ailing body and denied they helped him to hit a baseball. 73, by Barry Bonds, San Francisco Giants ( NL ), 2001 ( 162 game schedule ) In part due to 9 / 11 terrorist attacks, the then - recently set record of only three years by McGwire, and Bonds ' poor relationship with the media and some fans, Bonds ' record setting was not as publicized as the previous chases. Bonds was initially chased closely by Sosa and Luis Gonzalez of the Arizona Diamondbacks, but Gonzalez faded late and finished with 57, while Sosa finished closer with 64 to become the first player to exceed 60 home runs in three separate seasons. McGwire was not a factor during what would be his final major league season, as the injuries that had plagued him for much of his career finally took their toll, although he still hit at a pace that would have put him near 50 if he had played a full season. Bonds ' slugging percentage of. 863 broke the major league record set by Ruth in 1920. As happened with McGwire 's record, Bonds ' connection to steroids resulted in his being among the accomplishments questioned in the era. Home runs per game Number of home runs in the season divided by number of games in schedule ( not games played ) Average Name 0.451 Barry Bonds 0.430 Mark McGwire 0.390 Babe Ruth ( 1 ) 0.383 Babe Ruth ( 2 ) 0.377 Roger Maris 0.350 Babe Ruth ( 3 ) 0.240 Ned Williamson 0.200 Babe Ruth ( 4 ) 0.140 Harry Stovey 0.100 Charley Jones 0.070 George Hall See also The Year Babe Ruth Hit 104 Home Runs References Jump up ^ Ham, Eldon ( June 26, 2013 ). `` Sosa - McGwire : The Shock & Awe Summer Of 1998 ''. CBS Chicago. Retrieved September 22, 2017. Jump up ^ See e.g. Michael Wilbon ( December 4, 2004 ). `` Tarnished Records Deserve an Asterisk ''. Washington Post. p. D10. External links Progressive Leaders & Records for Home Runs -- Baseball-Reference.com Major League Baseball records Baseball statistics ( types of records ) General Record holders Single - game records Single - season records Record breakers by season Records considered unbreakable Batting leaders Career Batting average On - base percentage Times on base Slugging percentage OPS Hits 3,000 club Progressive Singles Doubles Triples Home runs 500 club Progressive Extra base hits RBIs Total bases Walks Intentional HBP Strikeouts Games played At - bats Plate appearances Annual Batting average Doubles Triples Home runs RBI Season Batting average Triples Home run Progressive Game Home runs Hitting for the cycle Grand slams RBI Game Inning Hits Misc Consecutive game hitting streak On - base plus slugging Hits Home runs Doubles Triples RBIs Baserunning leaders Career Runs Stolen bases Annual Runs Stolen bases Game Runs Misc Runs Stolen bases Pitching leaders Career Wins 300 club Losses Games started Games finished Innings pitched Strikeouts 3,000 club Saves Complete games Shutouts ERA WHIP Walks Hit batsmen Wild pitches Batters faced Annual Wins Saves Shutouts Strikeouts ERA Game No - hitter Perfect game List of perfect games Strikeouts Game Inning Immaculate innings Misc Wins Fielding leaders Career Putouts 1B 2B SS 3B OF LF CF RF Errors 1B 2B SS 3B OF LF Assists Passed balls Annual Putouts Errors Managing records Wins and winning percentage Multiple stat records Triple Crown 20 -- 20 -- 20 club 30 -- 30 club 40 -- 40 club Other Consecutive games played Longest winning streaks Longest losing streaks Individual streaks Retrieved from `` https://en.wikipedia.org/w/index.php?title=List_of_Major_League_Baseball_progressive_single-season_home_run_leaders&oldid=837258195 '' Categories : Major League Baseball records Baseball record progressions Hidden categories : All articles with unsourced statements Articles with unsourced statements from February 2018 Articles with unsourced statements from June 2008 Talk Contents About Wikipedia Português Edit links This page was last edited on 19 April 2018, at 18 : 01. 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Question: what is the mlb single season homerun record
Answer: 73