Ice fishing may only be done inside of a Fishing Hut. A number of them can be found in Mystery Lake, and on the lake in Coastal Highway. Another hut may be found on Pensive Pond in Pleasant Valley, or by the Mountaineer's Hut in Timberwolf Mountain
The player will also need an item to chip through the ice hole within the cabin. A Hatchet, a Hunting Knife, a Prybar, or a Heavy Hammer are all adequate for the job. This will deplete some of the item's Condition.
The player will also need a Fishing Tackle in order to fish. Some of the ice fishing huts may have a fishing tackle inside of them, or the Hook and Line components needed to create one. Fishing Tackle may be created at a Workbench or in the radial menu. One hook and one line are required, and it takes 15 minutes.
After the hole is clear, the player can choose how long they wish to fish in one hour increments, similar to how the player sleeps. The longer they fish, the more likely they can catch a fish. Success is not guaranteed.
The fish the player obtains can be picked up or put back, like any item. However, a discarded fish cannot be retrieved again.
Mystery Lake and Pleasant Valley are freshwater fishing spots, and offer Lake Whitefish. Timberwolf Mountain is also freshwater, and has whitefish and Smallmouth Bass. Coastal Highway is saltwater, and offers Rainbow Trout and Coho Salmon. Bass and Salmon are very large fish, and the larger ones can provide over 1500 calories, even when cooked. They can be large enough for the It was THIS Big! Achievement.
The fishing line has a 10% chance to break when a fish is caught, and the player will stop fishing if they run out of lines. Higher skill level in Ice Fishing can reduce this chance of breakage.
The hole in the water will not ice over while it is in use, but it will freeze if unused. Like animal corpses, they will gradually freeze over. A hole that is partially frozen opens faster than a hole that fully frozen.
The player is vulnerable to the elements and possible attacks by Wolves while fishing. Some fishing huts have doors that will bar wolves and will provide protection against the wind. A Bear might notice the player, but cannot reach the player inside of the hut.