The adult stage (産卵期 sanranki) is the longest stage in a Tamagotchi's life span (besides an oldie). Adults are the final stage of Tamagotchi before retiring and turning into and oldie. Lots of things become available to a Tamagotchi when he/she becomes an adult. The matchmaker starts visiting them when they turn 6 or 7, and they can marry and have babies. In addition, new items may become available for use. In the v4 Tamagotchi, adults are able to get a job, and go to the work section in TamaTown. In most Tamagotchi versions, the sleeping times of an adult will also change.
The adult stage often lasts until the Tamagotchi turns ten. The Tamagotchi will then turn into an oldie. An oldie will remain on a Tamagotchi toy until it dies or returns home. Oldies can mate with oldies of the opposite gender to produce babies. On certain Tamagotchi versions, the mating of Otokitchi and Ojitchi will produce Oyajitchi (or on the Tama-Go, Tamagotchi iD, and TMGC+C, Grippatchi).