The 26-year-old is due to meet with the Premier League club to discuss personal terms.
The clock is ticking for him to make his debut in the derby match tomorrow with Allardyce concerned that the player hasn’t trained for several days while the two clubs negotiated the deal.
However, Allardyce is expected to be able to call on the striker for the trip to Tottenham Hotspur a week on Saturday.
Either match though represents a phenomenal stage upon which to make his first appearance – either English football’s most highly-charged derby or at Wembley Stadium.
The Turkey international attracted a lot of Premier League interest with Crystal Palace, West Ham United, and Newcastle United all reported to be monitoring his situation as the January window loomed.
However, it’s Everton who are proving to be one of the top flight’s more ambitious movers in the transfer market. Having spent heavily in the summer, the club is now backing new manager Allardyce with Tosun being his first major signing.
It’s expected that Tosun will join on a 4½-year deal.