The deadline for registering to vote is 5pm this evening.
Anyone who wants to have their say on February 8 must be on the supplementary register by close of business.
Thousands of people who turned 18 since last May's local and European elections who are being encouraged to check the register.
The same applies for people who want to register a change of address.
If they are not already eligible the process is downloading a form, getting it signed and witnessed at a Garda Station and then bringing it to their local councils office.
Even those who are still 17 but turn 18 by February 8 can have their say.
CEO of SpunOut.ie Ian Power is encouraging young people in particular to register.
"We've got a last chance to take action today to make sure that you can have your say in the general election," said Mr Power.
"What we are saying to young people is to check the register, see if you're registered or if you know you're not fill out the required forms."
Mr Power has reminded people to bring a form of ID when bringing your form to your local Garda station.
"Some local authority offices are organising for gardaí to be onsite to stamp forms so maybe give them a shout or check their social media ahead of time because it could save you a trip."
Meanwhile, the deadline for the nominations of candidates to get on the ballot paper for February 8 is also later today.