Indigo League arc
Largest time gap - Episode 18 (Beauty and the Beach) - 1061 days
Smallest time gap - Episode 43 (The March of the Exeggutor Squad) - 176 days
Orange League arc
Largest time gap - Episode 105 (Misty Meets Her Match) - 436 days
Smallest time gap - Episode 83 (Pallet Party Panic) - 310 days
Johto League arc
Largest time gap - Episode 207 (The Kecleon Caper), 208 (The Joy of Water Pokémon), 209 (Got Miltank?), 210(Fight for the Light!) - 408 days
Smallest time gap - Episode 247 (Will the Real Oak Please Stand Up?) - 155 days
Hoenn League arc
Largest time gap - Episode 390 (Date Expectations) - 415 days
Smallest time gap - Episode 278 (A Ruin with a View) - 107 days
Kanto Battle Frontier arc
Largest time gap - Episode 422 (Fear Factor Phony) - 337 days
Smallest time gap - Episode 459 (Aipom and Circumstance!) - 161 days
Diamond & Pearl
Largest time gap - Episode 472 (Dawn Of A New Era!) - 245 days
Smallest time gap - Episode 520 (Smells Like Team Spirit!) - 99 days
Best Wishes!
Largest time gap - Episode 708 (Enter Elesa, Electrifying Gym Leader!), 709 (Dazzling the Nimbasa Gym!), 710 (Lost at the Stamp Rally!), 711 (Ash Versus the Champion!) - 100 days
Smallest time gap - Episode 700 (The Club Battle Hearts of Fury: Emolga Versus Sawk!), 701 (Club Battle Finale: A Hero's Outcome!), 702 (Meowth's Scrafty Tactics!), 703 (Purrloin: Sweet or Sneaky?), 704 (Beheeyem, Duosion, and the Dream Thief!), 705 (The Beartic Mountain Feud!) - 149 days
Best Wishes! Season 2
Largest time gap - Episode 744 (All for the Love of Meloetta!), 745 (Piplup, Pansage, and a Meeting of the Times!), 746 (Expedition to Onix Island!) - 128 days
Smallest time gap - Episode 798 (Team Rocket's Shocking Recruit!), 799 (Survival of the Striaton Gym!), 800 (Best Wishes Until We Meet Again!), 801 (The Dream Continues!) - 72 days
XY
Largest time gap - Episode 804 (A Battle of Aerial Mobility!), 805 (A Shockingly Cheeky Friendship!), 806 (A Blustery Santalune Gym Battle!), 807 (Battling on Thin Ice!), 808 (Giving Chase at the Rhyhorn Race!), 809 (Grooming Furfrou!), 810 (Clemont's Got a Secret!), 811 (Mega-Mega Meowth Madness!), 812 (The Bamboozling Forest!) - 100 days
Smallest time gap - Episode 802 (Kalos, Where Dreams and Adventures Begin!), 803 (Lumiose City Pursuit!) - 2 days
XY&Z
Largest time gap - Episode 895 (From A to Z!), 896 (Love Strikes! Eevee, Yikes!), 897 (A Giga Battle with Mega Results!), 898 (A Fiery Rite of Passage!), 899 (Dream a Little Dream from Me!), 900 (The Legend of the Ninja Hero!), 901 (A Festival of Decisions!), 902 (A Dancing Debut!), 903 (Meeting at Terminus Cave!) - 114 days
Smallest time gap - Episode 928 (Analysis Versus Passion!), 929 (A Riveting Rivalry!), 930 (Kalos League Passion with a Certain Flare!), 931 (Finals Not for the Faint-Hearted!), 932 (Down to the Fiery Finish!), 933 (A Towering Takeover!), 934 (Coming Apart at the Dreams!) - 79 days
Sun & Moon
Largest time gap - Episode 942 (Alola to New Adventure!), 943 (The Guardian's Challenge!) - 18 days
Smallest time gap - Episode 945 (First Catch in Alola, Ketchum-Style!) - 171 days
Note:- The episode number is the cumulative of all episodes aired in japan
