If I am granted a WHA do I also need to apply for a visa / employment permit / other document?

US citizens who are granted a Working Holiday Authorisation do not need to apply for a visa or employment permit, but they must register with the Garda Naturalisation and Immigration Bureau or their nearest Garda Síochána District Headquarters Station as soon as possible after arrival in Ireland, and within a maximum of 90 days of arrival.

At time of writing there is a charge of €300 for registration.