The first two seasons of the live action shows will air on CITV and ITV breakfast.
Nickelodeon has secured peak time viewing slots for Victorious and Big Time Rush across ITV's terrestrial and digital channels.
33 episodes of Victorious and 49 episodes of Big Time Rush will show on breakfast weekend mornings on ITV1 and after school slots on CITV, as well as in HD.
The deal represents the continuation of the partnership between ITV and Viacom; CITV has previously aired Viacom shows like SpongeBob Squarepants and Drake and Josh.
Caroline Beaton, SVP, programme sales, Viacom International Media Networks, said: “Our clients around the world look for top performing programming which travels and resonates with kids no matter where they are and Nickelodeon’s latest hits, Victorious and Big Time Rush, really have it all.
“I’m delighted that we’re able to extend these two hit live action series to even more audiences, this time across the UK, through our long standing and fruitful partnership with ITV.”
Tina McCann, SVP and MD of Nickelodeon UK, said: “Victorious and Big Time Rush have been huge hits for Nickelodeon UK. Each features outstanding young talent who really engage with UK fans. Both shows feature friendship, music, dance, fashion and aspirational lifestyle that really resonate with our audiences. We are delighted to be bringing these properties to a wider market.”