The pair had deals which were due to expire on June 30 and both players are widely expected to leave the club this summer.
However, Spurs boss Jose Mourinho was hopeful Vertonghen and Vorm would commit for the remaining Premier League matches and the club confirmed on Monday morning that they have done so.
A club statement read: "We can confirm that defender Jan Vertonghen and goalkeeper Michel Vorm have agreed to extend their existing contracts with the club until the end of the 2019-20 season.
"Both players' contracts were due to expire at the end of this month and this extension means they will now be available to play for us for the remainder of the current Premier League season."
The news will come as a boost to Mourinho, who was already bemoaning the lack of options available to him in the belief a change in the league rules to allow five substitutes favours more "powerful" rivals.
Vertonghen has been linked with a move to Italy or Spain but Mourinho said he has no concerns about the centre-back being distracted by speculation over his next club.
"Jan is a fantastic guy, fantastic professional," Mourinho said. "His love for the club, his respect for the club, is never in doubt."
Spurs also said they have agreed to extend the loans of Danny Rose (Newcastle United), Kyle Walker-Peters (Southampton), Jack Clarke and Luke Amos (both QPR) Brandon Austin (Viborg) and Armando Shashoua (Atletico Baleares) until the end of their respective league seasons.