When you receive a dividend from an Irish company, you will get a dividend cert as follows: Gross income: €100 Dividend Withholding Tax: €20 Net dividend: €80 You put the €100 on your tax return and so you pay tax on that at your top rate. You then get a credit for the DWT of €20. Foreign dividends are all treated differently. No. You can set your losses and gains on directly held shares against each other. Unit linked funds have no right of set off against anything else. There is a Key Post on ETFs and no conclusion has been reached.