A mailer for biological samples comprises a substrate, the substrate being foldable into a main panel and a cover panel. The main panel has formed therein at least one swab member, the swab member suitable, in size, shape, and rigidity, to act as a swab for obtaining a biological sample. The swab member is foldable relative to the main panel so the tip of the swab member protrudes from an edge of the main panel and an edge of the cover panel folded over the main panel. A machine-readable code or an electronic device is disposed on the swab member.