A beverage cartridge includes a bottom wall and at least one sidewall forming a chamber in which a beverage can be prepared from a stored beverage product. The sidewall includes one or more pre-formed openings or openable portions. Openable portions may be scored lines or reduced-thickness lines or regions, which open to form exit paths for a prepared beverage when a compressive force is applied to the sidewall, such as by moving a portion of the bottom wall toward an upper end portion of the cartridge to deform the sidewall and open the openable portions. Where the sidewall instead includes pre-formed openings, these may be initially covered or sealed and provide existing exit paths for prepared beverage upon removal of the cover. Optionally, a filter element is provided inside the cartridge for retaining a used beverage product inside the cartridge as a prepared beverage exits from the cartridge.