The Mercury Prize-nominated singer took the stage with a six-piece band shortly after half past two on Saturday afternoon.
Katy B introduced each member of the band in turn after third song 'Movement', saying that her MC Tipper "comes with me everywhere and helps to get the crowd hyped up".
As their performance drew to a close, Tipper bantered with the crowd, getting them to cheer louder to mark Katy B's last festival show of the year.
"We told a crowd in Jersey that last week, but we lied - and they were louder!" he declared.
Katy B dedicated her final song 'Lights Out' to "anyone who's been in a club and the lights have come on but they're not ready to go home yet".
A light shower affected part of the site yesterday, with the temperature noticeably lower than on the first two days of the event.
Grandmaster Flash, Mercury Prize winner PJ Harvey, The Cure and Village People are among the acts due to play at Bestival later today.
Primal Scream will also perform Screamadelica in its entirety to celebrate the album's 20th anniversary.
Katy B's Bestival setlist was as follows:
- Broken Record
- Easy Please Me
- Witches Brew
- Perfect Stranger
- Katy On a Mission
- Lights Out
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Watch Katy B's 'Katy On a Mission' video below: