People are being warned they could face jail time if they take a selfie in the polling booth.
Voters are being reminded that it is an offence to give out any information from a voting booth which could be captured in a photo.
Offenders could face a €1,270 fine or six months in jail.
James Barry, returning officer for Dublin, said: "The security of the ballot may be impaired. You could have a photograph of the voter with their ballot paper, and the order in which they voted, and that would not be acceptable to us."