The 36-year-old goalkeeper joined from Burnley in November 2020.
The club has taken up the option to extend his deal until the summer of 2024.
The 25-year-old right-back has made 50 straight starts.
Saints confirmed on Tuesday that the Canada international is one of 14 players who will be leaving this summer as Steven MacLean revamps his squad.
The 31-year-old midfielder signed from Salford on a two-year deal last July.
The Staggies finished 11th in the table and will face Championship side Partick Thistle in the first leg of their play-off tie at Firhill on Thursday.
The 37-year-old winger moved to Easter Road last summer on a one-year deal but two long lay-offs restricted him to just 14 appearances.
The event will kick off at 3pm on Saturday 24 June and end the following afternoon.
The Steelmen offered new contracts to academy graduates Max Johnston and Dean Cornelius several months ago but their futures remain uncertain.
The 30-year-old midfielder suffered a calf strain against Queen’s Park but is fit again ahead of the Ross County clash.
The Tynecastle board are discussing the managerial vacancy this week.
Defender Kerr has extended his deal with the Dark Blues until 2025.
The 33-year-old midfielder has spent 10 years with his hometown club.
Livi have lost defenders Nicky Devlin and Jack Fitzwater this summer.
United’s demotion to the Championship was confirmed on Sunday.
The Rujgby Park club secured their cinch Premiership status on Saturday.
The Staggies face Partick Thistle over two legs, with a place in the cinch Premiership the prize for the winners.
Van Veen scored for the 11th successive game during Well’s 3-2 win over Dundee United.
The 52-year-old was a surprise appointment as Gary Bowyer’s successor on Monday.