Skating professionals Jayne Torvill and Christopher Dean will take up their duties on the judging panel once again, ITV announced.
They will be joined by two additional judges who have yet to be announced.
In a joint statement, Torvill and Dean said: "We are thrilled that Dancing On Ice is returning to ITV next year and delighted to announce our new roles on the judging panel.
"The show struck such a huge chord with the viewers ever since it launched in 2006, with many of them taking up skating as a result. We can't wait to be back on screen in 2018, with a bigger and better series for a brand new audience."
Schofield said people often tell him how much they miss the show, and added: "With the show so fondly remembered, it's exciting for us all to now have the chance to breath new life into the show, and of course spending an extra day of the week with Holly is the icing on the cake!"
His This Morning co-star, Willoughby, said she was "excited" to be returning.
She said: "Working with Jayne and Chris is always such an honour and it's even more special as it's the show that Phil and I first worked on together ... it's full of wonderful memories and I can't wait to make some new ones."
Willoughby was one of the original hosts of the show, but left and was replaced by Christine Lampard.
Her Dancing on Ice wardrobe - notably a white gown with a plunging neckline - often made headlines on the celebrity ice-skating show.
The last series in 2014 was won by former X Factor contestant Ray Quinn.
Dancing on Ice aired for nine seasons, with the last one in 2014 featuring former winners and contestants from the other eight series.
ITV's director of television, Kevin Lygo, said: "Dancing on Ice is a wonderful show for all the family, and weekends have not been the same without it in our schedule.
"I'm delighted Jayne and Chris are on board and on the panel, and Holly and Phil are hosting, and I think we're all very excited to be returning with some star-spangled skating in 2018."