Letters are a form of communication in the Animal Crossing series. It is present in all main series games, but absent from spin-off titles such as Happy Home Designer. Players have the ability to send letters to villagers, other players, the player's future self, and the Faraway Museum, and players may receive letters from villagers, other players, some special characters, Nintendo, and other entities, such as the Happy Home Academy.
Letters are delivered at 6:00 AM each day by Pete to the player's mailbox in every game except New Horizons where they are delivered at 5:00 AM each day by an unknown carrier. Letters can be sent via the Post Office in Animal Forest, Animal Crossing, and New Leaf; via the Town Hall in City Folk and Wild World; and via the Airport in New Horizons.
To send a letter, the player must first obtain stationery. The player can send letters to the following addressees: villagers in the player's town, other players in the player's town, the Faraway Museum (only in Animal Forest and Animal Crossing), and the player's future self. Sending letters to villagers increases friendship points with them.
Letters in Animal Forest, Animal Crossing, City Folk, New Leaf, and New Horizons have six lines on which a message can be written whereas Wild World only has four. Each letter begins with the a greeting and the recipient's name and ends with the author's name and signature. Villagers will notice spelling errors the player makes and may comment on them negatively if the letter comes up in conversation later.
The player can attach a gift to the present in the inventory screen. All items, with the exception of fish, bugs, turnips, deep-sea creatures, snowflakes, keys, and lost items can be sent as a gift, which increases friendship points furthermore. Gifts may be wrapped with wrapping paper for additional friendship points.
Finally, to mail the letter, the player must deliver it to Pelly or Phyllis in the Post Office (Animal Forest, Animal Crossing, New Leaf), Pelly or Phyllis in the Town Hall (Wild World, City Folk), or Orville in the Airport (New Horizons).
Letters will be received in the mailbox outside the player's house at the start of each day. Letters can be received from villagers, other players, some special characters such as the player's parents and Jack, businesses, Nintendo, and other entities such as the Happy Home Academy and the Faraway Museum.
Letters the player receives can either be tossed or stored via a storage system offered in either the Post Office (Animal Forest, Animal Crossing, New Leaf), Town Hall (Wild World, City Folk), or mailbox (New Horizons).