Bunny Day (Japanese: イースター Easter) is a spring event which is the Animal Crossing series equivalent of Easter. It was introduced in City Folk. It has a different date each year, but will always fall on Easter Sunday. Zipper T. Bunny hosts the event outside the Town Hall or Resident Services in New Horizons. It is the only time of year the player can obtain the Egg Series of furniture. Zipper is an animal in disguise; if the player walks away from them, Zipper will stop dancing and sigh, and, if spoken to from behind, they will reveal the zipper on their costume. Often Zipper murmurs things such as "My mask fogged up again", "Geez how many of these did I bury?" or "I can't wait until this is over..." When a player tries to speak to them from behind, they will say either "Hey! You were trying to look at my back, weren't you?" or "Like I said, please don't look!"
In City Folk
Keeping to the idea of Easter, the Bunny Day event revolves around an Easter Egg Hunting competition. 30 Easter eggs are hidden around the town, which can be opened to reveal either candy (18) or a Bunny foil (12). Zipper will exchange one Bunny foil per item of furniture from the Egg Series. The Villagers around town will not get involved in the events, but will talk about Zipper and finding mysterious eggs buried around the town. Each character gets their own set of eggs.
In New Leaf
In New Leaf, there are six types of eggs which can be found by fishing, diving, shaking trees, digging up holes, hitting rocks and shooting presents in the sky, making the event more challenging and varied. Inside the eggs are either candy, winning tickets or grand prize tickets.
If a player eats an egg that they find, they can find a prize ticket. Tickets can be exchanged for an item in the Egg Series, and Grand Prize Tickets can be exchanged for Zipper's picture. The only item in the Egg Series that can't be obtained by exchanging tickets is the Egg Basket. This is obtained by giving Zipper all six different types of eggs, which is the first thing he asks for.
In New Horizons
Bunny Day is the first seasonal event to occur after New Horizons's release, and unlike in previous installments, has a "prep week" leading up to the event itself. On the first day of prep, which is the Sunday proceeding Bunny Day, Zipper appears on the island to tell the player about the event and give the Bunny Day bed recipe; if the player misses Zipper, the recipe will arrive in the mail the next day.
During the week of preparation, eggs will begin to appear on the island. In total, there are 6 types of eggs to collect, Sky (found hanging on multicolored balloons), Water (found via fishing), Leaf (found in groups of 3 on trees and needs to be shaken off), Stone (found by hitting a rock with a axe or shovel), Earth (found in the ground like fossils), and Wood (found occasionally by hitting a tree with a axe). These eggs are used to craft items in a new series, the ¨Bunny Day Series.¨ Like in New Leaf, the eggs can be eaten, and in New Horizons eating an egg provides stamina in the same way as eating any fruit.
Players can also learn unique DIY recipes for a hat, dress, and shoes themed around each type of egg after collecting a certain amount of eggs of that type. Collecting all of the egg-themed costume recipes unlocks the recipe for Egg party hat and Egg party dress.
These DIY recipes can be found in a few different ways:
- In presents tied to multicolored balloons in the sky (the same ones that drop sky eggs), needing a slingshot to get them. This seems to be the most efficient way of gaining recipes as about 1/3 of the multicolored balloons will be a recipe.
- In a multicolored variant of the message in a bottle called an Egg message bottle.
- From villagers who upon seeing the player have an ! above their head and run towards them.
- Four recipes (Bunny Day bed, Bunny Day arch, Wobbling Zipper toy, and Bunny Day wand) can only be obtained from Zipper himself.
On Bunny Day, Zipper will be present in the Resident Services plaza and all villagers will be dressed in egg costumes when they are outdoors. The player can obtain the Bunny Day arch recipe by speaking to Zipper. From then on, Zipper will also allow the player to trade in 3 of any type of egg for 1 of any other type, and also exchange 1 of each type of egg together for a Bunny Day basket furniture item, which has no DIY recipe.
Upon finding and crafting every single Bunny Day DIY recipe, including the Bunny Day arch, talking to Zipper again will reward the Wobbling Zipper toy recipe. After crafting that recipe and returning to Zipper for a third time, the player will receive the final prize of the event: the Bunny Day wand recipe.
For more information, see the Egg series.
The following furniture can be awarded by Zipper T. Bunny for exchanging foils of tickets.
Bunny Day Series
For more information, see the Bunny Day series.
Instead of exchanging tickets to Zipper in New Horizons for furniture, the event causes several recipes to be obtainable via special rainbow balloons or messages in bottles during the week preceding Bunny Day. These recipes can only be crafted using eggs found during the same event period, and once every recipe is obtained, the rainbow balloons will no longer give out recipes and the rainbow bottles will cease to appear.
Additionally, the DIY recipe for the Bunny Day bed can be received upon meeting Zipper T. Bunny on the island before the day of the actual event and the Bunny Day arch DIY on the day itself. After either encounter, Zipper T. Bunny will instruct the player to craft every DIY project from the Bunny Day series by the time Bunny Day takes place. After completing his mission, the player is rewarded with a DIY recipe for the Wobbling Zipper Toy. Crafting this and showing it to Zipper will result in the player receiving a DIY recipe for the Bunny Day Wand. Villagers may also approach the player to give recipes for the Bunny Day bag and Bunny Day crown.
If all the event's goals were completed on a previous Bunny Day, Zipper will congratulate the player anyways and give them a Bunny Day wand. Beside the DIY projects the player can request a Bunny Day Basket from Zipper on Bunny Day if they have one of each egg type in their pockets.
- There is an uncommon bug in New Leaf that will cause 2/3 of the rocks generated on Bunny Day to turn real afterwards. This can cause serious issues, such as forbidding access to certain parts of town such as the beach. Be sure to break all fake rocks before the day is over to cease this from happening. It has been reported that time traveling to a day after Bunny Day, then loading the game, then turning off the system without saving, can fix this issue. 
- On April 1st of 2018, for the first time ever, two events (excluding the Fishing Tourney and Bug Off) were on the same day. These were April Fool's Day and Bunny Day.
- In New Horizons, the initial spawn rates for eggs, in particular Wood Eggs, Sky Eggs, Stone Eggs, and Sea Eggs, were tweaked several days after Zipper T. Bunny's initial visit following fan backlash of these eggs replacing more valuable items such as crafting material and fish. This change in the rate of egg appearances doesn't apply on the day when Bunny Day itself is held.
- In the original Japanese version of Animal Crossing, the event is called simply "Easter" as with its real-world counterpart. Nintendo of America avoids using the names of Christian holidays, opting to rename Easter to Bunny Day, and also Christmas to Toy Day. However, less overtly religious holidays like Halloween retain their real-world name in U.S. versions of the game.