The 24-year-old could make the switch to east London in an estimated £15million deal - and his former club Rochdale could make over £4m as part of a sell-on clause.
Hogan's transfer could be one of the first big moves of the January transfer window - so who could follow him to the top flight?
If Chelsea wanted to loan teen sensation Tammy Abraham to a top-flight club, he has no recall option in his loan deal at Bristol City, while Steven Caulker is injured and highly-rated defender Lewis Dunk is unlikely to leave high-fliers Brighton.