The judge set 100,000-euro (USD 118,000) bail for the six other Catalan politicians who had been jailed in early November, and ordered their passports to be confiscated.
The six were expected to leave jails near Madrid later in the day.
Meanwhile, Catalan ex-president Carles Puigdemont and four of his separatist allies heard that they will be judged on whether they can be extradited from Belgium to Spain on December 14, exactly one week before the election.
Puigdemont's defense lawyer, Paul Bekaert, insisted that the Spanish charges weren't punishable in Belgium and thus there were no grounds for extradition.
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"We also highlighted the danger for the impediment of their human rights in Spain," he said.
Whatever decision is made on December 14, two appeals will be possible and a final ruling could well come only after the December 21 election called by Spain's central authorities, in which Puigdemont is leading his pro- independence party's campaign.
The early election is an attempt to find a democratic way out of the nation's worst crisis in nearly four decades. But the vote is shaping up as a plebiscite between those for and against independence, with polls predicting a close race between the two camps.
Adding to the uncertainty, a Supreme Court judge decided today to uphold the preventive jailing of ousted Catalan Vice President Oriol Junqueras, who tops the ticket for the left- republican ERC party.
Campaigning officially begins at midnight today, and in the hours before that moment Catalan pro-independence groups hope to stage protests in front of town halls across the region against the Supreme Court's decision on the detained separatists.
Today's developments once again exposed deep splits among Catalans. Pilar Gonzalez, a 76-year-old housewife walking her dog in Barcelona, said the jailed Catalan political leaders were "political prisoners."
But 53-year-old contractor Jose Luis Aguirre said the attempt to unilaterally break away from Spain "is an act that cannot be allowed."