A quarter of a million people have applied to put their names on the electoral register since the sign-up deadline to vote in the general election, according to official figures.
People who registered to vote after 20 April were not eligible to vote on May 7, meaning thousands would not have been able to participate despite registering during the campaign period.
Those who signed up just days after polling day will also have to wait at least a year for the opportunity to vote in any election.
The 250,000 people who have signed up since the deadline number higher than the 184,000 people who voted for the Democratic Unionist Party, parliament’s joint fourth biggest party with eight MPs.
The Electoral Reform Society, which campaigns for reform of the voting system, said the UK was behind other countries, including Canada and some US states, that allow voters to register on the same day as the election.
“Britain needs to look at introducing same-day registration and expanding opportunities for people to register whenever they interact with the government – including pensions, benefits, and tax,” Katie Ghose, the society’s chief executive, told the Independent.
Such provisions have been found to increase turnout at elections by as much as eight per cent in some cases.
“The fact that 250,000 people tried to register to vote after the deadline for the General Election shows there is a massive appetite for people to have their say,” she added.
General election 2015: Polling day
General election 2015: Polling day
1/16 General election 2015
Nuns arrive to vote at a polling station at St John's Church in Paddington, London
2/16 General election 2015
A voter leaves the White Horse Inn in Priors Dean, also known as the 'Pub with no name', which is part of the East Hampshire constituency and acts as a local polling station on the day of the election
3/16 General election 2015
General view of inside the White Horse Inn in Priors Dean
4/16 General election 2015
People cast their votes as a man uses a punch bag in the East Hull Boxing Academy, which is being used as a polling station in Hull
5/16 General election 2015
Penny Higbee waits to greet voters at her home in Routh, East Yorkshire, which is being used as a rural polling station
6/16 General election 2015
Voters in Ironbridge, Shropshire, arrive to cast their vote at The Iron Bridge Tollhouse
7/16 General election 2015
A voter arrives at the North West Ambulance Service Station at Milton Green, Cheshire, which is being used as a polling station as Britain goes to the ballot box
8/16 General election 2015
A polling station has been installed in a launderette in Oxford
9/16 General election 2015
SNP candidate for the Gordon constituency and Former First Minister Alex Salmond with first time voter Nicki Falconer, and her family, (L-R) Mackenzie, Nicki, Skye, Alex Salmond and Keiran at their local polling station in the Gordon constituency in Ellon, Scotland
10/16 General election 2015
Prime Minister David Cameron and wife Samantha after casting their votes at Spelsbury Memorial Hall, Witney
11/16 General election 2015
Liberal Democrat leader and Deputy Prime Minister Nick Clegg and his wife Miriam Gonzalez Durantez arrive at Hall Park Hill Community Centre to cast their votes, in Sheffield
12/16 General election 2015
Labour Party leader Ed Miliband and his wife Justine Thornton leave the polling station at Sutton Village Hall in Sutton after casting their votes in the 2015 general election in Doncaster
13/16 General election 2015
First Minister of Scotland and leader of the SNP Nicola Sturgeon, votes with her husband Peter Murrell in Glasgow, Scotland
14/16 General election 2015
Ukip leader Nigel Farage arrives to cast his vote for the South Thanet constituency in Ramsgate
15/16 General election 2015
Plaid Cymru leader Leanne Wood arrives at a polling station in Penygraig, Rhondda, Wales
16/16 General election 2015
Green Party leader Natalie Bennett after casting her vote at Ossulston Tenants' Hall, London
“250,000 people is a quarter of a million missed opportunities … at a time of disillusionment with politics, we need to seize every opportunity for people to get involved.”
Those who registered after the deadline will have to wait until next year to vote when some local and devolved elections are taking place. The next general election is not expected to be until 2020.
The figures on the number of people who had registered since the deadline were stated in a parliamentary answer by John Penrose, the minister for Constitutional Reform.
Turnout at the election was 66.1 per cent, up by about one per cent on 2010.Reuse content