LisaH

It is my understanding that foreign withholding tax on dividends paid on shares held in an ISA is unrecoverable, i.e. we can't deduct it from other tax or declare it as a loss. Please correct me if I'm wrong. So, when making an investment decision, it would be good to know how much tax will be withheld. I've got some odd things going on in my account. Most companies traded in the US are withheld at 15%, but for some reason Canadian Pacific is taxed at 25.4%, and Regal-Beloit is not taxed at all (though it was at 15% previous to Nov. 2018). I've got two German companies, PNE AG and Energiekontor; Energiekontor is taxed at 26.3%, PNE was also, until 2019 when it dropped to 0%. Is there any logic to this? And is there any way of knowing in advance what the rate will be? So far I've had one dividend payment from an Australian company, untaxed, can I assume they all will be? I've had one from Ireland at 20%, and one from the Netherlands at 15%. Any insight would be welcome.