Animal Crossing New Horizons allows time travel as a game mechanism. You can time travel in the game by setting the clock on your Switch before saving and restarting the game. Many players first assume that time traveling is “cheating.” However, the game is designed with time travel in mind. The creators do not discourage it and say they expect players to time travel. Many tasks in the game would take years to complete without time travel.
There are only a handful of negative consequences of time travel in ACNH. Time traveling after buying turnips is especially dangerous, but there can also be minor problems with weeds, flower watering, star fragments, and cockroaches. There are no other bad outcomes that result from time travel.
When you travel forward in time, the game acts like you put your console down and didn't play at all for that time. When you travel backwards in time your entire island time travels with you. The game acts like the clock had been set wrong.
The chart below details how the game behaves when traveling both forward and backward. Unless otherwise stated, this chart assumes that you time travel by one day. A new day starts at 5:00 AM, so crossing that boundary even by a few minutes would be considered traveling one day.
|Flowers, weeds, and trees grow||Yes, and if you travel forward more than a week there will be tons of weeds||No, and any flower watering is canceled|
|Rocks filled with new ore||Yes||One rock will be be a new money rock, the other rocks are not replenished|
|Trees get more wood, wasps, furniture, and coins||Yes||No|
|Announcements from Isabelle||Yes||No|
|New mail from an island resident||Yes||No|
|Villagers contribute towards unfunded construction projects||Yes||Untested|
|Paid construction projects completed||Yes||Untested|
|Empty house plot reserved for random villager||Yes||Yes|
|Progress for villagers moving in and out||Yes||Untested|
|Bank account interest||Only if you travel forward to a new month, capped at 9,999 bells.||No|
|Star fragments on beach if you wished on shooting stars||Only if you time travel no further than the next morning, otherwise they are lost.||No, they are lost|
|New island vendor or visitor (KK, CJ, Redd, Sahara, etc)||Yes||Yes, if you limit yourself to time traveling one day at a time, it will be the same vendor that had been there on that day previously.|
|Ordered Nook catalog items delivered via mail||Yes||Delayed until the next day|
|Items from Gulliver, Flick, and CJ delivered via mail||Yes||Delayed until the next day|
|Items from Redd delivered via mail||Yes||Yes|
|New recipe bottle on beach||Yes||Yes|
|Talk to villagers more and give them another present||Yes||Yes|
|New villager crafting||Yes, only need to travel 3 hours||Yes|
|Bugs, fish and sea creatures change to those available at the new time||Yes||Yes|
|Seasons change as appropriate for the new date||Yes||Yes|
|Special events start or end (bug offs, birthdays, holidays, meteor showers, etc)||Yes||Yes|
|Turnips spoil||Only if you travel forward past Saturday||Yes, even if you only go backwards a few minutes.|
|You get bedhead and cockroaches||Only if you travel forward more than a month||No|
|Villagers may decide to move out without talking to you about it||No||No|