Monday is the last day to register to vote in the United Kingdom's parliamentary general election scheduled for May 7. Residents have until midnight to submit their paperwork in person or online. Metro reported that the process takes about five minutes to complete and can be done on a smartphone.

British citizens over the age of 16 can register, as well as Commonwealth, Irish or European Union citizens who live in the UK. To do so, people must enter their name, address, postal code and National Insurance number. They'll have to decide whether to be included in the open register, which contains information that companies can buy, according to the Guardian.

Registration was seen as especially important this year because about 800,000 people fell off the voter rolls in 2014, according to the Guardian. Mashable reported that about 7.5 million people had not yet registered for the May ballot, which the Financial Times called "the closest and most unpredictable general election in memory." 

On May 7, voters will elect 650 members of the House of Commons for terms of up to five years. Whichever party wins the most seats in the House of Commons will get the first crack at forming the new government, and generally the queen appoints that party's leader as prime minister. It is widely expected that no party will win an outright majority to govern alone. Major contenders include the Conservatives, led by incumbent David Cameron; Labour, led by Ed Miliband; the UK Independence Party, led by Nigel Farage; and the Liberal Democrats, led by Nick Clegg, who is currently in a coalition government with Cameron.

Several of those party leaders tweeted and released statements ahead of Monday's deadline to encourage voter participation. #RegisterToVote was trending in the country Monday on Twitter, and Google UK had a link to on its homepage. "The fact is, if you don’t vote, others will, and you will have to live with the result," Clegg said. "Political parties are not the same, they have different values, different priorities and different policies. If you care about what happens to the economy, the [National Health Service], education or the environment over the next five years, then voting matters."

Britons can register for the May 7 election here.