Theresa May has agreed a draft Brexit deal with the European Union, but now faces the next hurdle of getting it through a vote in Parliament. That Brexit deal vote is likely to take to place in December, but the exact date is yet to be confirmed.

With many rival factions among the 650 MPs that sit in the house, the picture is far from clear. Some we can rule out immediately, such as the Speaker, along with his three deputies, who do not vote in the Commons. And Sinn Féin’s seven MPs will abstain, putting the winning number of votes to approve May’s Brexit deal at 320.

The Democratic Unionist Party gives May a working majority under the confidence-and-supply arrangement signed in June last year. However, they are against any deal that sees Northern Ireland treated differently to the rest of the UK.

May will also need to secure the approval of Brexiteers and Remainers alike in her own party. She will also be hoping that Labour rebels will back her 585-page deal.

Here are how the parties are likely to vote in the Commons based on the latest information:


MPs: 315 

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There are 93 Conservatives that must vote with May because of collective responsibility, a constitutional convention that means they must vote with government decisions made in cabinet even if they do not privately agree with them.

Some estimates add another 60 or so MPs that will back the Prime Minister no matter what. There are around 110 Tory moderates who are likely to vote it through because they want to achieve Brexit without forcing an early election.

In all, May can probably rely on the support of at least 235 MPs from her party, although some estimates put that as high as 273.

How big that number will be will depend on the influence of high-profile Tory Brexiteers such as Boris Johnson and Jacob Rees-Mogg, who have both publicly slammed the deal.

The Pro-Brexit European Research Group reportedly has 80 MPs ready to vote down May’s Brexit deal, according to its chair, Jacob Rees-Mogg. Others claim this number is closer to 40.

This morning Brexit secretary Dominic Raab resigned in what will be seen as a big blow for May. Following her was Work and Pensions Secretary Esther McVey: more are likely to follow suit.

Likely votes for Brexit deal: 235 – 273 


MPs: 257 

Labour has said that it will vote down May’s Brexit deal if it did not meet its six tests for a Brexit plan.

It is unlikely that Labour will feel these conditions have been met, and Labour’s shadow Brexit Secretary Keir Starner has confirmed that the party will vote against May’s Brexit deal.

While there are around 235 who will vote against with its leader Jeremy Corbyn, there are a number of pro-Brexit MPs, such as Kate Hoey, who could vote in favour of May’s Brexit deal. However, other pro-Leave MPs, such as Dennis Skinner, have said that they will vote against May’s deal.

Some estimates put the number of Labour rebels as low as 5, others as high as 20.

Likely votes for Brexit deal: 5 – 20 

Scottish National Party

MPs: 35

Scotland firmly voted to remain in the EU and the SNP are almost certain to vote down May’s deal.

Its leader, Nicola Sturgeon, told ITV Border it’s important “we don’t allow ourselves to fall for the Prime Minister’s spin that a bad deal has to be accepted because the only alternative is no deal.”

Likely votes for Brexit deal: 0

Liberal Democrats

MPs: 12

The Liberal Democrats are firmly against leaving the EU and have positioned themselves as the party against Brexit.

However, Lib Dem MP Stephen Lloyd has reportedly told BBC Sussex that he will honour his General Election 2017 pledge and “vote for whatever Brexit deal is put before Parliament”

Likely votes for Brexit deal: 1 

Democratic Unionist Party

MPS: 10  

DUP leader Arlene Foster is against any deal that results in a physical border between Northern Ireland and the Republic. She has previously described the red line on the issue as “blood red”.

The party has also been against a Brexit deal that sees the Republic treated differently to the North in a so-called backstop arrangement. The deal says that a backstop has been agreed until another solution can be found.

Since then, the DUP have described the Brexit deal as “poor”. However, government sources are reporting that they are quietly confident they can be persuaded.

Likely votes for Brexit deal: 0 


MPs: 8

Suspended Tory MP Charlie Elphicke has said that he will oppose the deal. Andrew Griffiths, also a suspended Tory MP, has previously voiced support for the government’s Brexit proposals.

Former Labour MP Frank Field left the party in part because of his pro-Brexit stance and has said that he will “refrain” from making any comment on the deal until he has read it.

Independent Unionist Lady Hermon is against Brexit and has previously said that a return to a hard Irish border will lead to violence.

Former Labour MP and Brexiteer Kelvin Hopkins defied his party in July to back a government amendment to the Brexit bill. Fellow ex-Labour MPs Jared O’Mara and John Woodcock’s positions on the draft deal are unknown.

Likely votes for Brexit deal: 1 – 5

Plaid Cymru

MPs: 4

The Welsh party said last month that they will campaign “hard” to keep Britain in the EU. Its leader, Adam Price, has said he would back a referendum on the final terms of the deal.

Likely votes for Brexit deal: 0 

Green Party

MPs: 1

The Green Party has long been against Brexit and backs a People’s Vote. The single MP will almost definitely vote against the Brexit deal.

Likely votes for Brexit deal: 0

Brexit deal vote: How do the numbers add up?

A lot will depend on the actions of hardliner Brexiteers in the next few days and whether they trigger a vote of no confidence in May.

Even if May keeps the highest estimate of 273 Tory MPs onside, she is still 47 votes short of the 320 majority required.

If all 20 Labour rebels defy the party whip and vote the deal through, that still leaves her 27 short. If she can persuade all ten DUP members to vote for her deal, she will still need 17 more votes.

The numbers are far from certain and are constantly changing, but one thing is certain: May faces a huge uphill struggle, both to get the deal she has worked on for over a year and a half approved, and to keep her position as PM.