Most eligible adults are already registered - but almost one in five haven't put their names down.

The thousands who are not registered still have the chance to do so before January 11.

The elections for a new Assembly are scheduled to take place eight weeks later, on March 7.

A February 15 deadline to apply for postal and proxy votes, as well as election IDs, is also looming.

Seamus Magee, the head of the Electoral Commission's office in Northern Ireland, said: "This is a particularly busy time of year, but if people wish to vote in the forthcoming elections it's important that they act now to ensure they're able to vote come March 7 next year.

"There's still time to register to vote as long as people do so before January 11."

Applications for the register can be obtained by phoning 0800 0323 700 or by downloading from www.aboutmyvote.co.uk.

When the final trawl for new voters was conducted last November, around 82,000 people failed to put their names back on the register.

Under a new system, voters will now only have to register once every 10 years.

The changes allow regular updating of the register, but only people in the voting pool on January 11 will be eligible to cast ballots on March 7.

The drop in the number of registered voters has raised concerns among politicians.

On average, the register fell by 7% in Northern Ireland constituencies last year. West Belfast was the worst hit, with a drop of more than 15%.

Alliance deputy leader, Naomi Long MLA, backed Mr Magee's call for registration.

The East Belfast Assembly member stated: "Some people who are fed up with tribal timewasting and stagnation may not want to vote this time.

"By not voting or registering, they lose their voice and therefore don't have a chance to change things here.

"People should realise that they can make a real difference in Northern Ireland if they vote. It is essential that they register to vote and play a role in their society.

"The absolute deadline for registration is January 11 and I would appeal to people to return their forms so that they can make their voice heard."