Where to Find Unown

Generation 1

Red
Blue
Yellow

Generation 2

Gold

Inside Ruins of Alph (different forms appear when puzzles are solved)

Silver

Inside Ruins of Alph (different forms appear when puzzles are solved)

Crystal

Inside Ruins of Alph (different forms appear when puzzles are solved)

Generation 3

Ruby
Sapphire
Emerald
Fire Red

Inside Tanoby Chambers (different forms appear in different chambers)

Leaf Green

Inside Tanoby Chambers (different forms appear in different chambers)

Generation 4

Diamond

Solaceon Ruins (different forms appear in different rooms)

Pearl

Solaceon Ruins (different forms appear in different rooms)

Platinum

Solaceon Ruins (different forms appear in different rooms)

Heart Gold

Ruins of Alph B1F (different letters appear when puzzles are solved)

Ruins of Alph 1F (! and ? Forms; appears after finding all Unown letters)

Soul Silver

Ruins of Alph B1F (different letters appear when puzzles are solved)

Ruins of Alph 1F (! and ? Forms; appears after finding all Unown letters)

Generation 5

Black
White
Black 2
White 2

Generation 6

X
Y
Omega Ruby

Mirage Cave (South of Route 107)

Alpha Sapphire

Mirage Cave (South of Route 107)

Generation 7

Sun
Moon
Ultra Sun
Ultra Moon
Let's Go Pikachu
Let's Go Eevee

Generation 8

Sword
Shield
Brilliant Diamond

Solaceon Ruins (different forms appear in different rooms)

Shining Pearl

Solaceon Ruins (different forms appear in different rooms)

Legends Arceus

Crimson Mirelands: Solaceon Ruins, massive mass outbreaks (all 28 forms appear after completing the Unown Research Notes)

All over Hisui: one of each form

Generation 9

Scarlet
Violet

Unown Evolution Tree

Unown Alternate Forms

Unown B

Unown B
Psychic

Unown C

Unown C
Psychic

Unown D

Unown D
Psychic

Unown E

Unown E
Psychic

Unown F

Unown F
Psychic

Unown G

Unown G
Psychic

Unown H

Unown H
Psychic

Unown I

Unown I
Psychic

Unown J

Unown J
Psychic

Unown K

Unown K
Psychic

Unown L

Unown L
Psychic

Unown M

Unown M
Psychic

Unown N

Unown N
Psychic

Unown O

Unown O
Psychic

Unown P

Unown P
Psychic

Unown Q

Unown Q
Psychic

Unown R

Unown R
Psychic

Unown S

Unown S
Psychic

Unown T

Unown T
Psychic

Unown U

Unown U
Psychic

Unown V

Unown V
Psychic

Unown W

Unown W
Psychic

Unown X

Unown X
Psychic

Unown Y

Unown Y
Psychic

Unown Z

Unown Z
Psychic

Unown !

Unown !
Psychic

Unown ?

Unown ?
Psychic