Members of the House of Commons voted by 498 to 114 to advance the bill that would give Prime Minister Theresa May the authority to invoke Article 50 of the Lisbon Treaty -- the formal process of leaving the EU.
The size of majority in favor of triggering Article 50 on Wednesday means the bill is almost certain to become law. But a battle is expected next week when the bill returns to the House of Commons for detailed scrutiny in the committee stage. Opposition parties will then try to push through a series of amendments.
The House of Lords, the UK's upper house, will also need to approve the Article 50 legislation before it can become law.
Triggering Article 50 gives the UK two years to negotiate a separation deal with the 27 other members of the EU. May has said she wants to fire the Brexit starting gun by the end of March.
The Prime Minister told the House of Commons
that she would publish her detailed plan for Brexit in the form of a "white paper" on Thursday.
Divisions on both sides
The vote came after two days of debate that exposed divisions within the ruling Conservative party and the main opposition Labour party.
Former Labour Party leader Ed Miliband said he would support the measure but outlined major concerns over Brexit's impact on Britain's future global relationships -- particularly with the United States.
"I can go along with the Prime Minister that 'Brexit means Brexit,'" he said. "But I cannot go along with the idea that Brexit means Trump. And nor do I believe that is inevitable, and nor do I believe that is what the British people want either."
Former Chancellor of the Exchequer George Osborne, who was a vocal supporter of Britain remaining in the European Union, said he would nonetheless vote in favor of the bill to respect the democratic will of the people.
He warned that the Brexit negotiations were likely to be "rather bitter," and that the EU would seek large sums of money from Britain for projects undertaken while it was still a member.
"The negotiation will be a tradeoff, as all divorces are, between access and money," Osborne said.
Speaking at Prime Minister's Questions on Wednesday, May said MPs had a responsibility to respect the result of the June 2016 referendum, when Britain voted to leave the EU by 52% to 48%.
"We gave the right of judgment on this issue to the British people," she said. "They made their choice, they want to leave the EU."