With 118 votes in favour and 67 opposed, Switzerland's National Council greenlighted the deal, agreeing to release the 3.13 billion francs ($3.35 billion) needed to buy Saab's JAS-39 Gripen combat jets.
The vote marks an important step forward for the deal, which has hit several bumps amid concern in Switzerland over the spending cuts it will entail in other areas.
Swiss President Ueli Maurer told the lower house the Gripen purchase was "modest," noting that the 22 Gripen jets would replace 45 Tiger fighter planes, according to Le Matin newspaper.
Maurer also made note of the date of the parliamentary debate.
"Today is September 11th," he told the house.
"Nobody foresaw what happened in the US," Maurer said.
"This is why we must guard against unforeseen risks."
But Beat Flach, spokesman for the Liberal-Green party, said the principal dangers faced by Switzerland were not in the sky above the country but rather in the domaine of "IT wars".
It would therefore be "more intelligent" to approve air security agreements with neighbouring countries, he said.
While most MPs disagreed, many on the left saw the plane purchase as a waste of money at a time when Switzerland is not facing any military threats.
The public seems to agree.
Nearly two thirds, or 63 percent, of the Swiss polled for a survey published by the SonntagsBlick weekly on Sunday said they were opposed to the purchase of the Gripen jets.
A full 60 percent of those questioned meanwhile said they were opposed to Switzerland buying any new fighter jets at all, regardless of the seller.
The upper house of the Swiss parliament will now need to reconsider the deal after it approved the purchase in March but refused to release the funds needed.
If it too gives its full blessing to the deal, which is part of a larger order for the planes to be shared with Sweden in a bid to cut production costs, the agreement will likely still need to be put to a popular vote as part of Switzerland's direct democratic system.
According to media reports, that vote would likely take place during the first half of 2014.