Qwilfish locations — where to catch

In Paldea (Scarlet & Violet)

• Asado Desert — Walk
• East Paldean Sea — Walk
• East Province (Area One) — Walk
• East Province (Area Two) — Walk
• Glaseado Mountain — Walk
• North Paldean Sea — Walk
• North Province (Area One) — Walk
• North Province (Area Three) — Walk
• Poco Path — Walk
• South Paldean Sea — Walk
• South Province (Area Five) — Walk
• South Province (Area Four) — Walk
• South Province (Area One) — Walk
• South Province (Area Six) — Walk
• West Paldean Sea — Walk
• West Province (Area One) — Walk
• West Province (Area Two) — Walk

In Blueberry Academy (Scarlet & Violet – The Indigo Disk)

• Polar Biome — Walk

In Hisui (Legends: Arceus)

• Bathers' Lagoon — Walk
• Firespit Island — Walk
• Hideaway Bay — Walk
• Islespy Shore — Walk
• Lunkers Lair — Walk
• Ramanas Island — Walk
• Sands Reach — Walk
• Seagrass Haven — Walk
• Tombolo Walk — Walk
• Tranquility Cove — Walk

In Sinnoh (Diamond, Pearl & Platinum)

• Iron Island — Super Rod

In Johto & Kanto (HeartGold & SoulSilver)

• Route 12 — Super Rod
• Route 13 — Super Rod
• Route 32 — Good Rod, Old Rod, Super Rod

In Sevii Islands (FireRed & LeafGreen)

• Five Isle Meadow — Super Rod
• Green Path — Super Rod
• Memorial Pillar — Super Rod
• Outcast Island — Super Rod
• Resort Gorgeous — Super Rod
• Tanoby Ruins — Super Rod
• Trainer Tower — Super Rod
• Water Labyrinth — Super Rod
• Water Path — Super Rod

In Johto & Kanto (Gold, Silver & Crystal)

• Route 12 — Super Rod
• Route 13 — Super Rod
• Route 32 — Good Rod, Old Rod, Super Rod

Other games (7)

• Brilliant Diamond / Shining Pearl (Gen 8): Iron Island
• Sword / Shield — The Isle of Armor (Gen 8): Max Lair
• Sword / Shield (Gen 8): Bridge Field, Dusty Bowl, East Lake Axewell, Route 9, Galar Route 9, Giant's Cap, Hammerlocke Hills, Lake of Outrage, Motostoke Riverbank, North Lake Miloch, South Lake Miloch, West Lake Axewell
• X / Y (Gen 6): Kalos Route 8
• Black 2 / White 2 (Gen 5): P2 Laboratory, Route 4, Unova Route 4, Virbank City, Virbank Complex
• Black / White (Gen 5): P2 Laboratory, Unova Route 17, Route 17, Unova Route 18, Route 18
• Colosseum (Gen 3): Pyrite Bldg, Pyrite Cave

Qwilfish — full Pokédex entry