It emerged on Thursday evening that Snodgrass had opted for East London over a switch to Lancashire, and a move has now been sealed following discussions over personal terms and the completion of a medical this evening.
Jack Sullivan, the son of West Ham co-owner David Sullivan, initially confirmed the transfer on Twitter when posting: "robert snodgrass has signed for £10million. Our second signing for the window he has 7 goals and 3 assists in 20 PL games this year."
United then revealed further details of the transfer on their website, announcing that a three-and-a-half year deal had been signed by the 29-year-old.
Snodgrass joined Hull from Norwich City in 2014 and still had 18 months left to run on his deal at the KCOM Stadium.