The former Blackpool star has agreed a two-year deal with the Premier League club, but a fee between the two sides has yet to be agreed ahead of the 2014-15 season
The winger, who spent the second half of last season on loan at Crystal Palace, joins the club as a free agent, with the 21-year-old having run down his contract at Bloomfield Road.
Ince becomes Hull's third signing of the summer, following the arrivals of Jake Livermore from Tottenham and Robert Snodgrass from Norwich, but the two clubs have yet to agree a fee for the player.
Due to his age, Hull are required to pay a compensation fee to Blackpool but that figure could be settled by a tribunal should the clubs fail to reach an agreement.
The son of former Manchester United star Paul, Ince scored seven goals in 23 matches for the Tangerines last season before joining Palace, where he scored once in seven outings.