: Players who pre-ordered the game were guaranteed entry into the closed beta starting September 24, 2015.

: This version featured the iconic House, Hereford Base, and Consulate maps. Some players still find "old codes" today, allowing them to explore the original 2015 menus and art style, though the servers are long dead. Rainbow Six Mobile Beta (2022–2026) The mobile version has had ongoing tests:

: Ubisoft launched an interactive "Field Training" website where completing tactical exercises rewarded users with a beta key.

: The primary method was through Twitch Drops . Players had to watch the Siege X Showcase or participating content creators for at least 30 minutes to receive a code.

: Featured maps like Border and introduced the "Rainbow Initiative" battle pass.

: Once the drop was claimed, users linked their Ubisoft and Twitch accounts. An email was then sent to confirm participation and allow users to select their platform (PC, PS5, or Xbox Series X|S).

: This beta featured a new 6v6 mode , a visual overhaul, and the massive "Dual Front" map that introduced respawns—a first for the franchise.