In previous games, there were only four stores and they were all owned and managed by Tom Nook, with Timmy and Tommy working as assistants in Nookington's in the furniture department. However, in New Leaf, his nephews now own the franchise with a total of five stores while Tom Nook owns and manages Nook's Homes, a real estate agency.
The Gardening Store, which is owned by Leif, is built next door to all Nookling stores from when the store is added to the Town. When the Nookling Store is upgraded to a T.I.Y., the Gardening Store is merged together to create one building with one entrance for each store.
Selling items to any of the Nookling stores will give the player 20% less money than at Re-Tail, as Timmy and Tommy resell the item to Re-Tail and take a cut of the sale price of any item.
- Main article: Catalog
Aside from selling items in the store, the Nook twins give the player access to their own personalized catalog, from which the player can order any item that they have held in their pockets. Anything that was ever held there will be featured, but rare items, Fossils, fish, gyroids, etc. cannot be ordered. When purchased, an item will arrive by mail in about five hours. The player can order as many items as they may want. If the player buys more than ten, the player will have to come at a later time since the maximum capacity of the mailbox is 10.
The catalog becomes available when the player has upgraded to T&T Mart. From then onward the player can have access to the Catalog.
- Main article: Nookling Junction
Nookling Junction is the first incarnation of the Nookling Stores. It is normally open from 8 a.m. to 10 p.m., unless the player enacts either the Early Bird or Night Owl town ordinance, with earlier or later opening and closing times respectively.
It is very similar in appearance to Nook's Cranny, which appeared in previous games in the Animal Crossing series. This may mean it shares a similar history of being an old gardening shed which once belonged to Tortimer when he was Mayor of the Town. It resembles a shed made with wooden planks and metal sheeting for a roof. It is also the only Nookling Store to have a traditional hinged door, with the other stores having automatic or revolving doors.
The player must have spent 10,000 Bells towards their mortgage, 12,000 Bells in the store, and have lived in their town for 10 days before Nookling Junction will upgrade to the T&T Mart store.
- Main article: T&T Mart
T&T Mart is the second of the Nookling store upgrades. In order for the store to expand, the player must spend 12,000 Bells worth of items at Nookling Junction and have waited 10 days of the Town's creation in order to upgrade. It is the only Nookling store to be open until midnight each day, and even later if the player has chosen the Night Owl opening times under the town ordinance, which keeps it open until 5:00 A.M.
The store is similar in appearance to Nook 'n' Go, which appeared in the previous Animal Crossing series of games. It has automatic doors and a mostly glass façade. It is also the only Nookling store to have a sign on a pole, with the other stores having their signs on either the roof of the building or attached to the front.
- Main article: Super T&T
Super T&T is the third expansion of the Nookling stores. To upgrade to this store, the player must spend at least 25,000 Bells at T&T Mart and have had it open for a minimum of 10 days. The Gardening Store must also have been constructed in the town, and have been open for a minimum of 10 days. It is not open as long as the T&T Mart, but can be made to stay open until midnight if the player has chosen the Night Owl option in the town ordinance.
The store is similar in appearance to Nookway by retaining the green features, glass facade, flat roof and automatic doors. It also has the furniture leaf sign on the roof.
The store also introduces the player to Melody paper, a type of stationery in which the player can now add a tune to the letter, as well as write a message and add a present. Super T&T also now has enough space to hold another fortune cookie or another type of stationery.
To upgrade to T.I.Y., the player must spend at least 50,000 Bells and have the store open for at least 21 days.
- Main article: T.I.Y.
T.I.Y. is the fourth Nookling store in the game, with the previous store being Super T&T and the upgrade being T&T Emporium. To upgrade to the T.I.Y., the player must spend a total of 50,000 Bells in Super T&T and 21 days have passed since the opening of the store.
A noticeable change from the outside of the store is that the Gardening Store and the Nookling stores are now merged together into one larger building with two entrances, with one for each store. Leif still manages his store. The building is now red and retains the glass frontage from the previous two stores. It also now has one K.K. Slider album every day behind the fortune cookies.
To upgrade to T&T Emporium, the player must spend 100,000 Bells, completed four Gracie Fashion Checks at a satisfactory level and have the store open for 30 days before the option to upgrade is made available.
- Main article: T&T Emporium
T&T Emporium is the largest and final expansion of the Nookling stores. To upgrade to this store the player must have spent at least 100,000 Bells in T.I.Y. and have successfully completed 4 Gracie's Fashion Checks at a 'Satisfactory' level at minimum. T.I.Y. must also have been open for at least 30 days. It has a reduced number of opening hours due to the size of the building and the variety of items available. It opens from 9:00 A.M. to 9:00 P.M. under regular operations, but can have altered opening and closing hours depending on the town ordinance, making it close at midnight if the Night Owl option is chosen or open at 6:00 A.M. if the Early Bird option is selected.
The Gardening Store is now a part of the Nookling store franchise, with no separate entrance on the front of the building.
- If the player's town anniversary happens on the same day that a Nookling store is being remodeled, if Timmy or Tommy show up, they will be wearing the new store's uniform.