Maddison, 26, who has won three caps for England and helped the Foxes win the FA Cup in 2021, is set to undergo a medical at Spurs on Wednesday.
Maddison scored 10 Premier League goals last term but was unable to prevent the club from slipping to relegation.
Overall, he scored 55 goals and provided 41 assists for the Foxes and his creativity will be a welcome addition to a Spurs squad that has lacked a playmaker since the departure of Christian Eriksen in 2020.
Newcastle have also previously attempted to sign Maddison but appear to have turned their attention to AC Milan’s Sandro Tonali this summer.
Tottenham signed Italian goalkeeper Guglielmo Vicario from Serie A side Empoli on Tuesday and have also made Sweden midfielder Dejan Kulusevski’s loan move from Juventus permanent since the arrival of new manager Ange Postecoglou.