Tax on dividends

I signed up for AIB Online share dealing last September and bought a few thousand euro's worth of shares with an Irish company. I recently received a small dividend of €16 for these shares (for some reason the dividend was payed into my bank account even though I filled in a form asking for the dividend to be reinvested to buy more shares in the future). I know its only a small sum of money but how much tax should I pay on this dividend? My annual income from work is €34k but I will receive around another €8k from overtime and bonus. Also which form do I fill out when sending off this payment?

Form 12 has a space to declare Irish dividend income. It will be taxed at the marginal rate given your other income. They mightn't actually collect it from you though because the amount is so small.