Collins, 29 has made 69 league appearances for United since signing from Yorkshire rivals Leeds United in January 2011 and has signed a new two year extension with the option of a third year.
The Scottish defender told sufc.co.uk; "There are many factors why I wanted to stay and not least because I love it here. We've got a good side, the club is great, the management are fantastic to work with and I think I'm thriving."