The Hammers have been working on a number of full-back deals in recent weeks, but Wan-Bissaka has remained their number one target.
Agreeing a deal with Manchester United has proven difficult, while it has also been suggested the Hammers feel Wan-Bissaka should be given a payoff by the Red Devils to help the move happen.
Personal terms has also been flagged as an issue due to the amount of money Wan-Bissaka earns at Old Trafford.
West Ham are continuing to speak to Manchester United about the fee and the structure of the payments which would be due.
Wan-Bissaka stands ready to make the move and the Hammers will hope they can get the deal over the line soon.
The defender is into the final year of his Manchester United contract and would be able to move as a free agent next summer if he sees it out.