British nationals living overseas are being encouraged to nominate a friend or relative back home to vote in the next general election rather than rely on a postal vote.

With heightened expectation that Boris Johnson will call a snap general election possibly as early as October or November electoral administrators are trying to mitigate the risk of disenfranchisement and are advising people to consider a proxy vote.

Tower Hamlets, one of the councils that has contacted voters, outlined how little time authorities have if an election is called with the bare minimum five weeks’ notice.

“With the above in mind, we are encouraging our overseas electors to consider proxy voting,” it said in its email, with a link to the website with the registration form.

Councils and campaigners want to avert a repeat of the electoral debacle in May when postal votes arrived too late to be counted for the European parliamentary elections. The delays led to accusations that Britons abroad were denied the vote and to calls for a public inquiry and an investigation by the Electoral Commission.

Islington council told its overseas registered voters in an email: “If a snap election is called, the timetable for this election will be shorter than usual. Therefore there is a risk that overseas voters will not receive their postal ballot packs with enough time to return them to use by the close of the poll.”

Q&A How do I register to vote in the 2019 general election? If you want to vote in the general election on 12 December but haven’t yet registered – bad news. It is too late. However, you can still register online so you don’t miss out next time. And let’s face it, if the election results ends up being close, we could be having another one sooner than you think. Here’s how to get yourself registered for next time. To vote in a UK general election you must: Be 18 or over on the day of the election.

Be a British, Irish or qualifying Commonwealth citizen.

Be resident at an address in the UK (or a British citizen living abroad who has been registered to vote in the UK in the last 15 years).

Not be legally excluded from voting. You also need to be on the electoral register. You only have to register once, but will need to re-register if you have changed your address, name or nationality. The forms can be completed online. You may need details of your national insurance number and your passport if you’re a British citizen living abroad, and want to vote in England, Scotland or Wales. If you need help, you should contact your local Electoral Registration Office. You can use this service to find the address if you live in England, Scotland or Wales. If you live in Northern Ireland you need to contact the Electoral Office for Northern Ireland (EONI). Show Hide

It said it wanted to make voters aware of the risk and “therefore encourage you to consider a proxy vote instead”.

Anyone can be appointed a proxy voter as long as they are also registered and eligible to vote.

The appointed proxy must vote at their friend or family member’s designated polling station but do not need to do so physically as they can also apply to cast their proxy vote by post.

This widens the possibilities for voters now living overseas who may have registered in a town to which they no longer have ties.

“Say, I am registered in Cheltenham and I move to France. My proxy must go to the polling station in Cheltenham, but I can nominate a proxy, say, in London and then that person in London can apply to Cheltenham for a proxy postal vote. All my proxy has to do is phone the council in the area I’m registered in and they will help them set it up,” said Laura Lock, deputy chief executive of the Association of Electoral Administrators.

Proxy vote appointments can be accepted up to 5pm six days before an election. A postal proxy has to be registered by 5pm 11 days before a postal vote. But Lock said overseas voters id not have to wait for an election to be called to register a proxy.

The campaign group British in Europe (BIE) said it was strongly advising its members who could still vote “to register now in case of a snap election and to request a proxy to avoid perennial problems with postal ballots”.

The problem for council teams tasked with administration of elections is that they are bound by strict rules, which can hamper the efficacy of the postal vote system.

It is widely expected that a general election will be called with the minimum notice of 25 working days, or five weeks. But councils cannot finalise ballot papers and postal packs until 19 days before the election when nominations close.

The packs and ballot papers then have to be printed, meaning postal votes might not go out until 10 or 12 days before an election, said Lock.

Liz Read, electoral services manager at Coventry council, said: “For all voters it is important to give people the ability to make a choice. The more time you have the better. With a parliamentary election that is not scheduled, even the polling cards can’t go out until we have a date. That has implications for all voters, so we are urging overseas voters to look at their options now.”

Overseas votes could be key in an election expected to be a proxy second referendum on Brexit. There are an estimated 1.4 million overseas voters, more than double the difference between the no and yes votes in the referendum. But overseas voting records show poor turnouts.

House of Commons library data show there were a record 285,000 registered overseas voters in the snap election in 2017.