The Portugal under-20 international was second top scorer in the country's second tier with 14 goals in 32 appearances in his first season as a professional. At 6'3", he will add another physical presence to the Toffees' front line.
Speaking to the Daily Mail in March, Silva had expected a £650,000 switch to be agreed at the end of the campaign.
“I didn’t expect things to happen so quickly," Silva said.
"I’ve had chances and I’m very happy with what I’ve done.
“If I go for 700,000 Euros [£650,000], like they say, it would be good income for the club and I’d be happy about it.”The centre forward will move to Merseyside right away before joining up with the Everton squad at the start of July for the pre-season tour to Australia.
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