From the information that I have been able to gather, Tax remittance rules for non-domiciled apply only to assets like shares, income property, rent, etc. but not to bank deposits, ETFs or gains from Foreign currency. If you buy 100€ of BMW shares with IB in Germany and sell them at 200€ there is no CG tax payable in Ireland on the 100€ gain unless remitted to Ireland, nor on the dividends. If you leave 100€ in the IB deposit account and get 100€ interest , your 100€ gained are subject to DIRT (and possibly PRSI) in Ireland (not CG) and the remittance basis does't apply for that.