# Major League Baseball Reliever of the Month Award

Major League Baseball (MLB) honors its best relief pitchers with a Reliever of the Month Award for one pitcher in the American League (AL) and one in the National League (NL) during each month of the regular season. These awards have been issued since 2017. From 2005 to 2013, MLB honored a single relief pitcher across both leagues with the Delivery Man of the Month Award during each month of the regular season.

## Awards by month

MLB previously introduced a Reliever of the Year Award in 2014, awarded to one reliever in the American League and one in the National League. In 2017, MLB added a monthly award, also given to one reliever in each league, for each month of the regular season. The award was sponsored by The Hartford, a Connecticut-based investment and insurance company, from inception through the 2020 season.
The below table lists monthly winners; a number in parentheses indicates the instance of winning the award, for players who have previously won.
| Year | Month | American League | American League | National League | National League | Ref. |
| Year | Month | Player | Team | Player | Team | Ref. |
| 2017 | April | Cody Allen | Cleveland Indians | Greg Holland | Colorado Rockies | |
| 2017 | May | Craig Kimbrel | Boston Red Sox | Greg Holland (2) | Colorado Rockies | |
| 2017 | June | Roberto Osuna | Toronto Blue Jays | Kenley Jansen | Los Angeles Dodgers | |
| 2017 | July | Edwin Díaz | Seattle Mariners | Brad Hand | San Diego Padres | |
| 2017 | August | Álex Colomé | Tampa Bay Rays | Corey Knebel | Milwaukee Brewers | |
| 2017 | September | Aroldis Chapman | New York Yankees | Sean Doolittle | Washington Nationals | |
| 2018 | April | Edwin Díaz (2) | Seattle Mariners | Josh Hader | Milwaukee Brewers | |
| 2018 | May | Blake Treinen | Oakland Athletics | Brad Hand (2) | San Diego Padres | |
| 2018 | June | Edwin Díaz (3) | Seattle Mariners | Kyle Barraclough | Miami Marlins | |
| 2018 | July | Edwin Díaz (4) | Seattle Mariners | Felipe Vázquez | Pittsburgh Pirates | |
| 2018 | August | Edwin Díaz (5) | Seattle Mariners | Héctor Neris | Philadelphia Phillies | |
| 2018 | September | Blake Treinen (2) | Oakland Athletics | Corey Knebel (2) | Milwaukee Brewers | |
| 2019 | March–April | Shane Greene | Detroit Tigers | Kirby Yates | San Diego Padres | |
| 2019 | May | Aroldis Chapman (2) | New York Yankees | Josh Hader (2) | Milwaukee Brewers | |
| 2019 | June | Liam Hendriks | Oakland Athletics | Josh Hader (3) | Milwaukee Brewers | |
| 2019 | July | Tommy Kahnle | New York Yankees | Seth Lugo | New York Mets | |
| 2019 | August | Aroldis Chapman (3) | New York Yankees | Felipe Vázquez (2) | Pittsburgh Pirates | |
| 2019 | September | Brandon Workman | Boston Red Sox | Brent Suter | Milwaukee Brewers | |
| 2020 | July–August | Liam Hendriks (2) | Oakland Athletics | Kenley Jansen (2) | Los Angeles Dodgers | |
| 2020 | September | Mike Mayers | Los Angeles Angels | Devin Williams | Milwaukee Brewers | |
| 2021 | April | Matt Barnes | Boston Red Sox | Mark Melancon | San Diego Padres | |
| 2021 | May | Liam Hendriks (3) | Chicago White Sox | Ryan Tepera | Chicago Cubs | |
| 2021 | June | Lou Trivino | Oakland Athletics | Josh Hader (4) | Milwaukee Brewers | |
| 2021 | July | Raisel Iglesias | Los Angeles Angels | Jake McGee | San Francisco Giants | |
| 2021 | August | Emmanuel Clase | Cleveland Indians | Devin Williams (2) | Milwaukee Brewers | |
| 2021 | September | Liam Hendriks (4) | Chicago White Sox | Camilo Doval | San Francisco Giants | |
| 2022 | April | Jordan Romano | Toronto Blue Jays | Josh Hader (5) | Milwaukee Brewers | |
| 2022 | May | Clay Holmes | New York Yankees | David Bednar | Pittsburgh Pirates | |
| 2022 | June | Emmanuel Clase (2) | Cleveland Guardians | Edwin Díaz (6) | New York Mets | |
| 2022 | July | Jordan Romano (2) | Toronto Blue Jays | Edwin Díaz (7) | New York Mets | |
| 2022 | August | Emmanuel Clase (3) | Cleveland Guardians | Edwin Díaz (8) | New York Mets | |
| 2022 | September | Emmanuel Clase (4) | Cleveland Guardians | Camilo Doval (2) | San Francisco Giants | |
| 2023 | April | Félix Bautista | Baltimore Orioles | Josh Hader (6) | San Diego Padres | |
| 2023 | May | Alex Lange | Detroit Tigers | Camilo Doval (3) | San Francisco Giants | |
| 2023 | June | Félix Bautista (2) | Baltimore Orioles | Craig Kimbrel (2) | Philadelphia Phillies | |
| 2023 | July | Félix Bautista (3) | Baltimore Orioles | Devin Williams | Milwaukee Brewers | |
| 2023 | August | Andrés Muñoz | Seattle Mariners | Raisel Iglesias (2) | Atlanta Braves | |
| 2023 | September | Clay Holmes (2) | New York Yankees | Tanner Scott | Miami Marlins | |
| 2024 | April | Mason Miller | Oakland Athletics | Ryan Helsley | St. Louis Cardinals | |
| 2024 | May | Emmanuel Clase (5) | Cleveland Guardians | Robert Suárez | San Diego Padres | |
| 2024 | June | Carlos Estévez | Los Angeles Angels | Ryan Helsley (2) | St. Louis Cardinals | |
| 2024 | July | Emmanuel Clase (6) | Cleveland Guardians | Tanner Scott (2) | Miami Marlins/San Diego Padres | |
| 2024 | August | Josh Hader (7) | Houston Astros | Raisel Iglesias (3) | Atlanta Braves | |
| 2024 | September | Emmanuel Clase (7) | Cleveland Guardians | Ryan Helsley (3) | St. Louis Cardinals | |