Eddie Howe is well stocked for goalkeepers at Newcastle, with Loris Karius recently extending his short term deal, and Darlow has been tipped to move on.
The shot-stopper has now given the green light to a loan move to Championship side Hull, but it will only be completed late on deadline day.
Newcastle are in action in the second leg of their EFL Cup semi-final tie against Southampton on Tuesday and Darlow will not complete the move until it finishes.
The goalkeeper was on the bench for the first leg of the tie, which Newcastle won 1-0.
Darlow has made just one appearance for the Magpies this term, in the EFL Cup against Tranmere Rovers.
He will be keen to return to playing regular first team football during his loan stint at Hull and is no stranger to the Championship, having turned out 140 times in the division.
Hull currently sit in 15th place in the Championship table and beat QPR 3-0 at home on Saturday.