Auch für Counter-Strike: Source sind jetzt die Gäste-Pässe über Steam verfügbar (wie bereits bei Day of Defeat: Source). Besitzer von CS:S können fortan einen Bekannten einladen, der das Multiplayer-Actionspiel drei Tage lang und ohne Kaufverpflichtung antesten kann. Im Steam-Untermenü "Games" können die "Guest Passes" verwaltet werden.

Steam Guest Passes are now available to all owners of Counter-Strike: Source. Just like the Steam Guest Passes recently issued for Day of Defeat: Source, all CS:S players now have the ability to invite a friend to their favorite online game. Upon receiving and activating the Steam Guest Pass, the invited friend has 3 days of Counter-Strike: Source play available to them for free, with no obligation to purchase. Guest Passes are another example of advanced service and functionality that can only be offered through Steam, a leading platform for content delivery and management.