The former Nottingham Forest man joined the Lilywhites in January 2013 on an 18-month contract which contained a clause allowing the club to extend his deal by 12 months.
Following Garner's impressive performances this campaign, the club has exercised the clause.
Manager Simon Grayson told the club's official website: "It is more good news. Earlier this week we confirmed the nine new deals and now we have confirmed Joe will also be part of the squad.
"We are building a team that wants to play for this club, wants to improve and who want to work hard and Joe is another example of that and we are delighted to be able to trigger this clause and continue to work with him."