The National Youth Council of Ireland is urging all young people to use the Supplementary Register of Electors to include themselves on the electoral register in time for election day.
A statement from the council said most young people are unaware of the supplementary register.
At least 60,000 first time voters are entitled to have their names added to the register but have not done so.
Voters can register up to 12 days before election day, excluding Sundays and Bank Holidays by completing a special form from a local authority office, a Garda station, library or post office.