Currently gamers can only play together online if they use the same system.
One of the first games to support cross-platform play will be Rocket League, which Xbox and PC gamers will be able to play together via Xbox Live.
There is "an open invitation" for other networks to collaborate, the tech giant said.
The announcement was made as the developers conference ID@Xbox takes place this week.
The collective represents 1,400 independent studios creating games for Xbox One and Windows 10 devices.
Director Chris Charla said that it was "up to developers" to support the feature, in a letter posted online.
"Xbox Live players will always have the option of choosing to play only with other Xbox Live players," he added.
Nintendo, Sony and Microsoft all operate their own online networks for multiplayer games, with Sony and Microsoft charging gamers a monthly fee.
"Cross-network play has been the number one most requested feature our community has asked for since Rocket League was first announced on Xbox One," said Psyonix, the studio behind Rocket League.
"Today's announcement is a dream come true."