|“||We see amazing players in Overwatch every day; now, you can officially celebrate them! When a match ends, take a look at players on both teams and endorse the players who made positive contributions to your matches. The world needs heroes: help create them!||„|
|~ PlayOverwatch website|
Endorsements are a social feature that is meant to reward and feature players for their good behavior.
At the end of the match, players can give 3 different types of endorsements to teammates, and 1 type to enemies. You can only repeatedly endorse a player every 12 hours.
A player can endorse 3 players per match, and giving out an endorsement grants 50 XP to the player that granted it.
The endorsement level is shown in the scoreboard for teammates, on your own career profile, and in the voice chat. The indicator for it is a circular meter that fills up with certain colors depending on the types of endorsements received, along with the endorsement level.
The endorsement level can decay.
Types of endorsements
Shot Caller 
This endorsement can only be given to teammates. "Players who lead or execute strategies on the battlefield can earn a Shot Caller endorsement." -Official PlayOverwatch site.
Good Teammate 
This endorsement can only be given to teammates. "You can reward those who work as highly effective team players with a Good Teammate endorsement." -Official PlayOverwatch site
This endorsement can be given to either teammates or enemies. "You can give Sportsmanship endorsements to people who are a positive influence in-game." -Official PlayOverwatch site
All players begin at endorsement level 1 and can progress to a max level of 5; every endorsement you receive impacts your endorsement levels. You will also receive a small amount of player experience for endorsing another player. Higher endorsement levels can help you get better groups in the Looking for Group tool.
You will receive Loot Box for level 2 | 2 Loot Boxes for level 3 | 3 Loot Boxes for level 4 | 4 Loot Boxes for level 5. During events, these will be Event Loot Boxes. These rewards are not sent out regularly, and not all players receive the Loot Boxes at the same time.rewards based on your endorsement level: 1
Maintaining your Endorsement Level
The trick of maintaining your endorsement level is to play Overwatch frequently and most importantly not leaving matches prematurely.
Your endorsement level can decrease if you do not continue to receive endorsements or leave games before they’re finished. Punishments within the reporting system may also strip players of their endorsement level and place them at level 0.