Dave Meltzer revealed on today's Wrestling Observer Radio that WWE is considering holding SummerSlam 2021 at Madison Square Garden.
"I’ve heard Madison Square Garden. Oh, I shouldn’t have said that…It may not be, but it’s under consideration. It’s not like it’s been announced or anything."
WWE rarely holds pay-per-view events at The Garden these days, due to cost and location. They have favored the Barclays Center in Brooklyn for many of their big PPV's over the last decade.