It was announced at the weekend that the two Premier League clubs had agreed an undisclosed fee for the one-cap England international, and Livermore has now signed a contract.
The 24-year-old, who enjoyed an impressive season on loan with the FA Cup finalists last term, said that he never had any hesitation in making the move permanent.
"I'm delighted to be joining Hull City on a permanent basis," he told the club's official website.
"I thoroughly enjoyed my season here on loan and I firmly believe that this club will keep on going from strength to strength. I made my feelings known that I wanted to come here permanently and once the two clubs had agreed the fee, it was very straightforward."
Livermore scored three goals for Hull in the last campaign and laid on two assists in the 5-3 FA Cup semi-final triumph over Sheffield United at Wembley.
The move offers some stability to a player who has had seven loan spells away from Tottenham in the past five years.
It is also a key piece of business for manager Steve Bruce, who will lead the club on their first foray into Europe next season.
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