If you are looking for Fortnite's Rarest Skins then we've got a full list of them right here. While the battle pass skins are unavailable, you will be able to get a chance at grabbing some of these in the item shop!
Rare skins in Fortnite has been a controversial subject. Players that have them don't want them to return because they want the reward of being around in the beginning of the game (OGs). Newer players obviously want to get a chance to grab all the skins they like.
Epic has made an interesting compromise for the Skull Trooper skin. This was a very rare skin and hadn't been in the shop for a year. When they brought it back, they gave OG owners of the skin a style that will not be available for people who buy the skin new. This is a nice way to reward older players, while not keeping popular skins away from people who just got into the game.
Rarest Fortnite Battle Pass Skins
These are skins you CANNOT get anymore. They won't be back again unless Epic changes their policy completely. This set of skins includes Season 1 which wasn't technically a battle pass season. The first season had a "season shop" and you had to level your season level up so you could purchase the skin. This was obviously very early on in the game and before it gained its huge popularity.
These are the two skins from the Season Shop you could get during Season 1.
These skins are from Season 2 and while they aren't as rare as the ones above, they are still pretty scarce.
Both Season 2 back blings, and it's a shame the Black Shield won't be back because it's great. During Season 1 I'm pretty sure back bling didn't even exist yet.
These are Season 1 gliders and quite rare. You will likely go your entire Fortnite career and never see them, and while this is partially because they are rare, it's also because they are kind of ugly!
A couple of Season 2 gliders, these were later in the battle pass and a bit more rare than the earlier glider.
Raider's Revenge is from Season 1, and the other two are from Season 2.
Rarest Fortnite Item Shop & Other Skins
Now, these skins are ones you might actually have a chance to get. They were purchasable in the item shop at one point or another, and now that Skull Trooper has been re-released it's likely they will all come back at some point.
Now that the majority of Holiday skins have been added again to the item shop, we can pretty much officially say that there's not really going to be any reliably rare skins. Ghoul Trooper and Recon Expert are the rarest of the skins. Ghoul Trooper wasn't released again during Halloween, and Recon Expert hasn't been back in the shop since November 2017. I'm basing the list below on how often it has been in the shop and how long ago it appeared.
Rarest Promotional Skins
Promotional skins are cosmetics that you could only receive for a limited time during a specific promotion. This could be from Twitch Prime, PlayStation Plus, or from purchasing certain products like consoles and controllers. These are going to be inherently rare for the most part, but we'll likely only include ones that have been out for a while.