The historic vote in the House of Commons over Theresa May's Brexit deal will begin at 7pm.
MPs across our region are deciding whether to back the Prime Minister - or send her back to Brussels to try to gain more concessions.
Mrs May is widely expected to lose tonight's vote which could increase the risk of Britain heading out of the EU without a deal.
But with the prospect of no deal on the horizon, have opinions in the Calendar region changed since the area voted overwhelming in favour of Brexit?
Our reporter Chris Kiddey has spent the day in Boston, the most Eurosceptic town in the UK where over seventy five per cent of those who voted in the referendum wanted to leave.
Our reporter Lisa Adlam has spent the day in Harrogate - one of only three places in Yorkshire which voted to remain.