Foley has been linked to the yard for over 10 years but will now be going freelance, with Halford using the best available jockeys.
Halford told his website, www.michaelhalford.com: "There's been no falling out, we've just decided that Shane won't be automatic first choice and I'll be using the best available for the remainder of the season. I've spoken to all my owners and they are happy to go with that. Shane has been a great asset to us here and we've had some great days."
Foley said: "I've had a great run with Michael. I've ridden for him for over 10 years, but we had a chat last night and while I'm disappointed, there are lads out there a lot worse off than me.
"I hope to continue to ride for Michael when available and I'll be going freelance for the remainder of the season.
"I'd like to thank Michael and his owners for their support and I'm sure that we'll enjoy more success in the future."