Pokopia is set to release its first-ever downloadable content, Bubbly Basin, alongside a free base game update, marking a significant expansion to the life-simulation title. The paid DLC introduces an entirely new underwater biome along with exclusive Pokémon and building mechanics, and it represents only the first instalment of a planned three-part release.

The Bubbly Basin expansion pass is officially scheduled to launch on 5 August, though most North American regions will likely gain access during the evening of 4 August due to time zone differences. While Nintendo has not confirmed an exact launch time, releases for the Switch 2 typically go live at 9am Japan Standard Time, which would correspond to 1am British Summer Time on 5 August. The DLC adds a new underwater region with exclusive Pokémon such as Mudkip and Popplio, new habitats, underwater building using "Buoyant Blocks", watermelon crops, and additional features including Bubble Machines and a power-up for the Surf move.