- The 1916 Philadelphia Athletics had the worst winning percentage in MLB history.
- In 2024, the Chicago White Sox became the first team to lose over 120 games.
- Only two teams have ever posted a winning percentage below .250.
The teams with the worst regular-season records of all time didn’t come close to hitting the over on their MLB betting win totals. These teams endured seasons that are unfortunately written into baseball’s history books.
Below, I have ranked the worst regular-season records in MLB history based on their winning percentage.
What’s the Worst Regular Season Record in MLB History?
| Rank | Team Name | Winning Percentage | Year |
| 1 | Philadelphia Athletics | .235 | 1916 |
| 2 | Boston Braves | .248 | 1935 |
| 3 | New York Mets | .250 | 1962 |
| 4 | Washington Senators | .252 | 1904 |
| 5 | Chicago White Sox | .253 | 2024 |
| 6 | Philadelphia Athletics | .257 | 1919 |
| 7 | Detroit Tigers | .265 | 2003 |
| 8 | Pittsburgh Pirates | .273 | 1952 |
| 9 | Washington Senators | .276 | 1909 |
| 10 | Philadelphia Phils | .278 | 1942 |
Worst Major League Baseball Records
1. Philadelphia Athletics – 1916
Finishing with 36 wins is impressive when three of the 1916 Philadelphia Athletics combined for 14.2 bWAR.
Their eventual 36-117-1 record represented an improved winning percentage after they won just 20 of their first 100 games.
2. Boston Braves – 1935
Wally Berger was the only everyday hitter on the 1935 Boston Braves with an above-league-average OPS.
The Braves scored the fewest runs per game and had the worst wins above average from their pitching staff.
3. New York Mets – 1962
The New York Mets finished 40-120 in their first season in the majors. New York won 10 fewer games than their run differential indicated they should have won, and they allowed a league-worst 5.89 runs per game.
This was the first of four consecutive 100-loss seasons, but the Mets were competitive soon after and won the World Series in 1969.
4. Washington Senators – 1904
After starting the season a woeful 11-53, the 1904 Washington Senators did well to finish 38-113-6.
A team OPS+ of 79 and an ERA+ of 74 is not a winning formula. Washington remained in a rut until they won 91 games in 1912.
5. Chicago White Sox – 2024
Before the season, baseball odds at the BetMGM online sportsbook didn’t project the Chicago White Sox as a playoff team. I was pessimistic about their roster, but I didn’t expect anything like the 41-121 record they ultimately posted. Five wins from their last six games meant the season-ending record was better than it was on course to be.
— Chicago White Sox (@whitesox) September 29, 2024
The official X account stopped posting the scores with a few weeks left in the season. There were non-overlapping losing streaks of 21, 14, and 12 games. It was a historic campaign for the White Sox, and the argument can be made that they’re one of the worst MLB teams ever.
6. Philadelphia Athletics – 1919
Three years after posting the lowest winning percentage ever, the Athletics went 36-104.
After winning three World Series in four years, Philadelphia finished last in the American League for seven consecutive years.
7. Detroit Tigers – 2003
Like the White Sox, the 2003 Detroit Tigers won five of their last six games. Prior to that, they had been on a 13-51 slide.
Subpar on both sides of the ball, Detroit was carrying several subpar hitters, and their pitching wasn’t any better. They finished 47 games behind the division-winning Minnesota Twins in the AL Central.
8. Pittsburgh Pirates – 1952
Honus Wagner retired from coaching before the season, Ralph Kiner was involved in a contract dispute, and ownership decided to name an opening-day roster with 13 rookies.
The Pittsburgh Pirates’ 1952 season was doomed to fail. Kiner, the highest-paid National League player at the time, underperformed and received death threats.
9. Washington Senators – 1909
The second Washington Senators entry on this list comes just five years after they had a .252 winning percentage.
An 8-12 run to end the season left the Senators 42-110-4. Between Aug. 11 and Sept. 15, they won just three games.
10. Philadelphia Phils – 1942
Philadelphia had to cope with a lot of losing in the first half of the 20th century. Three of the lowest winning percentages in MLB history came from the City of Brotherly Love between 1916 and 1942.
After the Athletics struggled in the 1910s, the Philadelphia Phils endured a rough patch in the 1930s and 1940s. This was the second of three seasons in seven years with a sub-.300 winning percentage.