As Domo points out, funds accumulated by you while you have been in the US will not be subject to Irish income tax if remitted into the country. One thing you should watch though is that if your US account is interest bearing you should transfer funds accumulated prior to your return to Ireland to a separate account. Otherwise if interest is earned on the account after your return to Ireland you will have a mixed fund account and any remittances from that account will be considered to come first from the interest earned post arrival in Ireland and that portion will be taxable.