Polling station
The deadline to register to vote in the London mayoral election is 18 April Getty

There is less than a month to go before 12 candidates compete to succeed Boris Johnson as the next Mayor of London. With the deadline to register to vote just days away, here is everything you need to know to be able to vote on 5 May.

Who is eligible to vote?

You can vote in the elections for the Mayor of London and the London Assembly if you have registered to vote, live in London and will be at least 18 years old on 5 May 2016.

You have to be a British citizen, a European Union citizen or a Commonwealth citizen who has or does not require leave to remain in Britain. British citizens living overseas cannot vote in the Mayor of London and London Assembly elections.

British citizens living overseas cannot vote in the Mayor of London and London Assembly elections.

When do you have to register by?

The deadline to register to vote is Monday 18 April. If your local registration office has not received your application by then, you will not be able to vote – this is something to bear in mind if you are planning to register by post.

You will need your National Insurance number, your date of birth and your address to register online here. You can also register by post by printing out and filling in the registration forms. You can track down the contact details of your council's electoral registration office using this link and return the forms to them. It is also possible to ask your local electoral registration office to post the forms to you, if you do not have access to a printer.

Polling station
You can vote in person at your local polling station, by post or by proxy Getty

Once you have registered to vote for the Mayor of London election, you will also be able to vote in the London Assembly elections. You will automatically receive your polling card or your postal pack.

What ways can you vote?

There are three ways you can vote in the elections – you can vote in person at your local polling station, by post or by proxy.

To vote in person: You will be send a poll card that includes details of where your nearest polling station is, which will be the only place you can vote. The polling station will be open between 7am and 10pm on Thursday 5 May for you to go and vote.

To vote by post: If you are a registered postal voter, you will be sent three ballot papers around a week before 5 May. Make sure you return them before this date in the envelopes that are provided. If you run out of time, you can deliver it by hand at any polling station in your borough.

To vote by proxy: This means you can apply to have someone you trust to vote on your behalf.

Who can apply for a proxy vote?

You must have a reason to apply by proxy. You can apply if: you are away on holiday on voting day; you have a physical condition that means you cannot go to the polling station; your work will prevent you from going to the polling station; you are attending an educational course; you are a British citizen living overseas; or you are a member of the Armed Forces or a crown servant.

Usually, the deadline to register to vote by proxy is six days before an election. To act as your proxy, the person you choose must be 18 and over (or 16 in Scotland) and are registered to vote individually.