The 21-year-old is set for his second experience of League Two football after a loan spell with Wycombe Wanderers in 2012/13.
A Scotland under-21 international, Archer returned to Spurs to play 14 times for their development side last season and also travelled with the first team squad to some of their Europa League fixtures.
Cobblers manager Chris Wilder told the club website: "Jordan is here to challenge for a first-team place.
"It is important to have competition, and Jordan is in the frame to battle with Matt Duke for a first-team spot."