The initial fee is understood to be worth around £10million, with a further £10million potentially due through various add-ons and performance-related incentives. The 21-year-old spent last season on loan at Oxford United, where he scored 11 goals and provided four assists in 44 Championship appearances.
That form followed a standout spell in Tottenham's youth ranks, having originally joined from Sheffield United in 2022. Lankshear scored 23 goals for the Under-21 side that won the 2023-24 Premier League 2 title, a campaign that saw him named the competition's player of the season.
He made his senior debut for Spurs in October 2024 against Ferencvaros in the Europa League, scoring his first senior goal in that match before being sent off in his very next appearance in the competition away at Galatasaray.
Should the move be completed, Lankshear would become Middlesbrough's fourth signing of the summer, following the free transfer arrival of Miles Peart-Harris from Oxford, along with Jeremy Sarmiento from Brighton and Kyle Joseph from Hull City.
The deal comes shortly after Middlesbrough's sale of midfielder Hayden Hackney to Everton for around £16million. The Teesside club will also receive a significant sell-on fee should Chelsea complete their reported £117million signing of former Middlesbrough forward Morgan Rogers, providing further financial firepower as they continue to rebuild their squad this summer.
The fact personal terms remain unresolved leaves some uncertainty over whether the move will ultimately go through, with reports suggesting other clubs have retained an interest in Lankshear despite Middlesbrough's agreement with Tottenham.
However, the size of the package involved reflects the regard in which the young striker is held after his prolific loan spell at Oxford, and Middlesbrough will be hopeful of getting the deal over the line before the transfer window progresses much further, giving new arrival time to settle before the new Championship campaign gets under way.