Fowler will put pen to paper on the deal next week after impressing since his arrival from Manchester City in January.
Benitez said: "This is fantastic news. Robbie has done really well and he deserves this.
"He has scored some vital goals for us and he has worked really hard. I am delighted to have him with us for next season. He is an important member of our squad."
Hardly a shock. It makes me happy though.
