With 331 votes in favour, 304 against and 11 abstentions, parliament approved holding a decisive vote on Thursday. M, KD and S voted yes, other Swedish parties no.
This opens the way for extending regulations that expired last spring, creating legal uncertainty about the possibilities of searching for perpetrators.
Today's vote is about whether we want to protect our children or the perpetrators, Tomas Tobé (M) urged his colleagues before the vote.
"Everyone who votes yes today is voting for mass surveillance," countered German colleague Mary Khan from the far-right AfD party.
The battle over EU rules has been festering for many years, with accusations from online activists that the scrutiny is too far-reaching.
