General election 2015: 'No repeat' of polling day queues
The chaotic queuing seen at some polling stations at the 2010 general election will not be repeated this time around, the head of the Electoral Commission has said.
Jenny Watson said there was now a "safety valve" that meant people in a queue as polls closed could still vote.
More than 1,200 people were left queuing as polls closed at 22:00 on election night in 2010.
Police were called to deal with angry voters who had been turned away.
Voters in Sheffield, Manchester, Birmingham, Liverpool, Newcastle, parts of London and Surrey were affected.
A subsequent report by the Electoral Commission blamed the problems at 27 polling stations in 16 constituencies on "poor planning, the use of unsuitable buildings, inadequate staffing arrangements and the failure of contingency plans".
Giving evidence to MPs, Ms Watson said the "safety valve" had already been used in local elections.
"If you should find yourself in a queue at 22:00 you will be able to vote," she told the Commons Political and Constitutional Reform committee.
"It has been tested, we know that as a safety valve it works.
"It's no substitute for good planning, and I do not know of any returning officers who would treat it as a substitute for good planning, but as a safety valve it does exist."
Ms Watson also told the committee letters were being sent to every household in an attempt to increase the number of people registered to vote. Last week, the Ccommission said the number of entries on the electoral register had dropped by 920,000 between March and December last year.
This figure had been a "snapshot", and two million applications to register online had been registered since 1 December, she added.
How to register to vote
You can register once you are 16 although you will only be able to vote on 7 May if you are 18 or over on the day.
If you are a citizen of another EU member state or Commonwealth country living in the UK, and unsure whether you are entitled to vote in the general election or local elections check the Electoral Commission website.
You can register to vote online through the government's gov.uk portal. The process takes five minutes and you will need your National Insurance number.
If you are unsure whether you are already registered or want to update your details, contact your local electoral registration officer to find out. You can also register to vote by post.