ITV News Presenter Julie Etchingham reports
This week is the National Voter Registration Drive, which last year saw 441,500 people registering to vote.
As part of the campaign, which is supported by Bite the Ballot, people are being encouraged to register to vote.
To vote in elections and referendums, you need to be on the electoral register.
If you live in England, Scotland or Wales you can register online by visiting the gov.uk website and following the instructions.
To register by post, you can download a form here.
You can also use the gov.uk website to update your name, address or other details on the electoral register, change your voting preferences and change whether you are on the open register.
If you live in Northern Ireland, you must use a different form, which can be found by clicking here.
You cannot register to vote if you are in the UK illegally.