If I were to invest in US domiciled ETF, using a roboadvisor or using a RSP, how are US/ Irish dividend withholding tax, other taxes and management fees calculated?

Hi,

You are subjected to 30% dividend withholding tax when you invest in US-domiciled ETF, even when using a roboadvisor or RSP. It is 15% dividend withouholding tax for Irish-domiciled ETF. (Both are not subjected to capital gain tax)

Most of the roboadvisor management fees are dependent on how much money you have deposit with them (etc. 0.5% of $1000 annually = $5), you can find out more about their fees and make a comparision here:

https://blog.seedly.sg/singapore-robo-advisor-i...

For RSP, the fees vary for different brokerage or banks and thus you will need to look out for one which meet your goals and comfort. You can also RSP quarterly or semi-anually to save some fees if your monthly RSP amount is minimal (I try to keep the fees below 0.5%) . ​​​