The under-23 captain makes the switch to south west London to link up with the League One side, in what will be his first move away from the club since signing for the Seagulls as a scholar in 2015.
Under-23 coach Simon Rusk said, “This move represents a good chance for Max to experience regular senior football in a competitive division.
“He has been a very important part of what the team have achieved over the last few seasons, and that’s been rewarded with recent first-team involvement and now this move.
“We will be keeping a close eye on his progression and wish him all the best for this season.”
Sanders skippered the under-23s in their Premier League 2 play-off victory over Aston Villa in the 2017/18 campaign, and made 14 league appearances for the team last term, as they sealed a third-place finish in the top flight.
The England under-19 international was named on the bench for the first team’s fixture with Liverpool in the Premier League last season, as well as in last week’s Carabao Cup victory over Bristol Rovers at the Memorial Stadium.
The midfielder will be ineligible for tomorrow night's Leasing.com Trophy game between Albion and AFC Wimbledon.