The electoral watchdog is investigating up to 1,000 complaints about people illegally voting twice at the general election on 8 June.
The Electoral Commission said there were “troubling” reports of double-voting, with 38 MPs raising concerns about the activity in their constituencies.
It is legal for students to be registered in university accommodation and in their home town, but they must vote only once.
The commission’s report said: “Although people may lawfully be registered to vote in more than one place in certain circumstances, it is troubling that some voters appear to have admitted voting more than once at the general election, which is an offence.”
It is working with police on how best to investigate the allegations and called for the government to consider ways of cutting the risk of abuse of voting rules.
The report also documented the rise in registrations of young voters, with nearly 2 million applying after Theresa May called the snap election.
About 500,000 more people were registered for the 8 June poll than for the 2015 general election, taking the electorate to a record 46.8 million.
A surge in young voters is credited with helping fuel support for Jeremy Corbyn.
About 70% of those trying to register to vote in the runup to the election were under 34 but most of these applicants were already on the register.
The Electoral Commission called for ministers to look at introducing a system to allow voters to check if they are already registered and to consider whether to adopt automatic registration schemes similar to the one used in Australia.
Sir John Holmes, chair of the Electoral Commission, said: “The size of the registered electorate for the general election demonstrates the UK’s strong tradition of democratic engagement, and reflects the hard work of all concerned.
“However, if we are to keep pace with modern habits and practice in a digital world, the electoral registration system must continue to evolve, and consider innovative solutions such as direct or automatic enrolment processes.
“These have the potential to deliver significant improvements to the accuracy and completeness of electoral registers as well as efficiencies for local authorities and the public purse.”
Labour MP Cat Smith, shadow minister for voter engagement and youth affairs, urged the government to be cautious when introducing any measures that could hinder voting.
“We welcome the Electoral Commission’s report, which shows that 46.8 million people were registered to vote at the 2017 UK general election – making it the largest electorate for a UK-wide poll,” she said.
“To build a healthy democracy we need active participation of all citizens, which is why the Labour party delivered a ground-breaking digital campaign which sought to maximise the number of young people registering to vote during the election period.
“Double voting is a serious crime and it is vital that the police have the resources they need to bring about prosecution.
“However, we urge caution when looking at measures to tackle this issue – a blanket ban on being registered at two addresses would exclude those who for reasons of work or study need to be registered in two places.”
