The newly promoted Premiership side have agreed to splash out on £2,100,000 which could rise to a total £3,000,000 after possinle add-ons.
Hulse is expected to arrive at Bramall Lane in the next day or so for talks on a three year deal.
Blades boss Neil Warnock told sufc.co.uk: "It has been a lengthy chase and I am delighted that it has ultimately been successful.
"I feel Rob still has a lot to prove but he has strengths which I am sure will compliment those of the strikers we already have."
The Blades boss is also keen to strengthen at the back and has taken Glasgow Rangers left-back Oliver Bernard on trial after the Scottish giants have told the Frenchman he can leave on a free transfer.