I searched the forum but could not find anything on this subject.
Let's say an Irish resident earns a living trading on forex on his own account from his home, and he is not employed by anybody. What sort of tax is he liable for?
Income tax and/or Capital Gains tax. You will be tax as a self-employed person and will have to submit annual returns. These can be prepared by yourself and submitted on-line using the Revenue On-line service or can be prepared and submitted by an accountant or tax advisor on your behalf.
If some of the gains come from trading in forex funds rather than directly in forex or warrants or similar derivitives then thses are taxed as income rather than capital gains.
I understand that the revenue have set a numerical limit on the amount of trades you can make in a given period before you are considered to be a trader. If you exceed that limit then you pay income tax.