According to Steam Database, via SteamCN, Steam Summer Sale 2019 will begin on the 25th of June 10
Like before, there will be special exclusive trading cards up for grabs during the sale and of-course a variety of wallet destroying discounts across almost every game in Steam’s massive collection.
There will be some competition this time around with Epic’s current Mega Sale just getting off the ground though it won’t be overlapping as the Mega Sale comes to close just a week before the Summer Sale opens. Still, even with their recent exclusive grabbing spree, Epic’s current lineup is hardly a match for what Steam has to offer.