UPDATE 11/21/16: Added an alternative way to catch Pikachu in the wild, as well as info about evolving into Raichu.
Pikachu has been a staple of Pokémon since the very beginning, becoming an instantly recognizable symbol for the series. It's no wonder people were desperate to find out how he could be caught in Pokémon GO, and it'll be wonder when people are also desperate to find one in Pokémon Sun and Moon.
That's where we come in.
If you've recently purchased Sun and/or Moon and are looking to grab a Pikachu to call your own but don't know where to start, we have you covered. Read on, why not?
Pichu And Pikachu Both Spawn On The First Island
Hey, did you know that Pikachu evolves from Pichu? Of course you did! (And if you didn't, don't feel bad.) The reason I'm pointing this out is because you can technically get Pikachu and Pichu from the same area — meaning, you basically have twice the chance of finding the Pokémon you're after (math wizards, please don't correct me on my embarrassing math).
Where you'll want to look is Melemele Island, which is the island on which your journey begins. There are two different locations on Melemele Island where Pikachu spawns, but I prefer the one right inside Hau'oli City. There are several more patches of grass here (Pikachu spawns in all of them), and it's located near shops and Pokémon Centers if you run out of Poké Balls or need to give your team a rest.
Now, the spawn rate isn't exactly great, but if you're really after a Pikachu, this is where to go. If you get tired, try again at a different time of day and don't fret — Pikachu's spawn location being in a low-level area pretty much guarantees a catch once you actually do encounter him.
Finally, the easiest trick to capturing Pikachu — thus, avoiding the need to level Pichu — is to find a Pichu in the wild and stall with moves that won't kill it. After long enough, the Pichu will call for an ally, and this ally has a chance to be a Pikachu.
If You're Ever Unsure About A Spawn Location, Check The Pokédex!
One of the really nice things about Sun and Moon is the ability to check a Pokémon's natural habitat, even if you haven't actually caught that Pokémon yet. You do, however, have to have seen the Pokémon to view this info in your Pokédex*.
Simply open up the Pokédex, find the Pokémon you're looking to catch, and then hit "A" to show where it can be found. Be sure to check each island, as several Pokémon — like Pichu and Pikachu — are native to only one island. In the event that the Pokédex says a Pokémon's habitat is unknown, this likely means it can't be caught in the wild. For example, Raichu's information lists no known habitat because you can only get one by evolving a Pikachu using a Thunder Stone (sold in a shop toward the end of the second island).
*The exception to this is QR codes, which we have more info on below.
You Can Share And Scan QR Codes To Add Pokémon To Your Pokédex
Another awesome feature in Sun and Moon is the ability to scan QR codes of specific Pokémon out of friends' Pokédexes and add that Pokémon's info to your own Pokédex. There's actually a bit more to QR codes (including the ability to unlock rare Pokémon), but for the purposes of this article, it'll only be something to worry about if you haven't encountered a Pichu or Pikachu and want that info in your 'dex.
Still, it's a feature you don't want to forget about and a great way to trade Pokémon between Pokédexes if you've seen something your friends haven't or vise versa. And yes, there's always the internet. But could you really sleep at night knowing you illegitimately acquired info for your Pokédex?
Yeah, didn't think so.
Is there a specific Pokémon you want to catch in Sun and Moon? What makes it an important catch for you?