The campaigns and debate around assisted dying have been unlike any other legislation – in part due to the free vote.
MPs have described this as the hardest decision in their political careers.
Hundreds of MPs have spent the last few weeks sifting through the evidence, emotions and ethical dilemmas of the bill, with much of the work playing out in town halls and community centres.
On the eve of the vote, neither side sounded super confident, political editor Chris Mason said – with both sides acknowledging there were lots of MPs who had not publicly said how they will vote.
And both sides say the debate could also prove crucial for some MPs, he added.
In the past few days Labour MP Jess Asato and Rebecca Paul, a Conservative, told the they plan to vote against the bill after polling their constituents and speaking to experts.
Paul said she was worried the healthcare system is too stretched to ensure protection for vulnerable people.
Asato said she cannot support the bill as it lacks sufficient safeguards against vulnerable people being coerced into taking their own lives.
Other MPs are drawing on their personal experiences. Labour MP for Monmouthshire, Catherine Fookes, said watching her father suffer through a painful terminal illness has led her to support the bill.