The Community Strategist at Naughty Dog wrote on the PlayStation Blog this week to reveal the dates for the Uncharted 4 Beta, which will commence on December 4th and will run through till December 13th.
We know you are all looking forward to hearing more about what’s new in multiplayer, what’s new with gameplay, and what new modes and maps you can expect. We’re planning a grand reveal that will answer many of your questions about Uncharted 4 multiplayer before the Beta goes live this December.
During this time members of the beta will be able to access parts of the games multiplayer ahead of the full games release. However to get in you do need a copy of Uncharted: The Nathan Drake Collection and a PlayStation Plus membership.
If you got those two then you are all set.
Uncharted 4 will release on October 9th for the PlayStation 4 exclusively.
Source: PS Blog