I agree with this. I've read quite a few posts where inaccurate advice was given by Revenue on the phone - this is the first in relation to gambling tax but that's because it's an uncommon query on the forums. I don't see why someone earning a consistent €12,000 per month is so unwilling to pay for advice and is resorting to unproveable phone calls instead. If I were on that boat, I'd be looking for the Revenue to give written confirmation and would also get one of the big accountancy firms to give the advice on letter-headed paper as well. The cost of the advice will be a drop in the ocean compare to the winnings. The argument from Fella seems to be "gambling winnings aren't taxable in Ireland" which is true. The question is, would the revenue consider what you are doing to be gambling? That's a lot tougher to answer. Comparing your arbitrage to JP McManus gambling winnings is a waste of time. McManus is a multi-billionaire and what he does is actual gambling. In a lot of cases, he bets large sums on his own horses to win. He doesn't tend to lay the horses he bets with other bookmakers or do anything else to remove the risk of the bet. A lot of his bets are for sums in the region of £100,000 and, like most gamblers I know, you only tend to hear about the winners.