The 2018 MLS season isn’t over and won’t be over for another two weeks, but the off-season will begin on Monday.
By 1:00 pm on November 26, the clubs that aren’t still in the playoffs - i.e. all the teams in MLS except Atlanta United, New York Red Bulls, Portland Timbers, and Sporting Kansas City (and 2019 expansion club FC Cincinnati, which doesn’t really have a roster to purge yet) - must notify the league office of the contract options they will be exercising and those players on expiring contracts who have received bona fide offers to renew.
Each club will be responsible for publicizing its own roster decisions, which can be expected to include a list of those players whose contract options are not being exercised.
This will likely be of greatest interest to FC Cincinnati, which will get its first significant clues regarding which players clubs are likely to protect from the Expansion Draft on December 11.
The mass roster purge will also also set the tone for initial speculation about the off-season priorities for all those teams not in the final four of the playoffs.
On November 30, there will be a second iteration of this exercise, restricted to the two losing teams from the Conference Finals. The MLS Cup finalists will announce their end-of-year roster decisions on December 9, the day after the MLS Cup final.