The number of people registering to vote surged to almost half a million on Monday as people rushed to apply before the midnight deadline.

Some 469,047 applications were made online and just less than 16,000 on paper, according to Cabinet Office figures.

It was the busiest day since the introduction of the new online system, the Electoral Commission said.

Large numbers of people also registered in the days running up to the deadline; a total of 118,505 on Thursday, April 16, 104,403 on Friday, April 17, 66,986 on Saturday, April 18, and 124,284 on Sunday (April 19).

Alex Robertson, from the Electoral Commission, said it was "absolutely fantastic" that more than two million people had applied to register to vote over the last few weeks.

He added: "On the day of the deadline we saw almost half a million people apply to register in just one day, the busiest day since the introduction of the new online system."

This is nearly as many as the half a million or so who registered in the weeks leading up to election day in 2010.

According to the Cabinet Office figures, most of those who registered to vote on Monday were in the 25 to 34-year-old age group (152,000), followed by the 16 to 24 bracket (137,000) and then the 35 to 44-year-olds (89,500).

Some 61,000 45 to 54-year-olds registered on the day and 28,500 in the 55-64 bracket. Just 11,100 65 to 74-year-olds registered on the last day and 5,303 over 75s.

The total size of the electorate will not be known until after May 7, the commission said, as the tallies are collated individually by councils.

In 2010 it was almost 45.6 million, the largest ever. The registers contained 1.35 million more names than in 2005 - an increase of 3.1%.