@Gep75 Unfortunately, you are asking for something no broker provides. This is not just a Trading 212 problem. Compare the advice given by the huge premium-fee Hargreaves Lansdown to those who use their platform. (If anyone should be able to admister dividend double taxation arrangements then they should.) However, they warn, “Due to the complexity of the tax regimes in other countries, HL Asset Management will not generally reclaim tax credits on dividends or other income on foreign securities.” Similarly, AJ Bell advise, “No, we do not offer a foreign withholding tax reclaim service”.
It is possible for a UK investor to reclaim German tax from the German tax authorities, reducing it to 15%, which equals the amount allowable as a credit against UK tax. Similarly, it can be done for France, Spain, etc. However, people complain that the paperwork is difficult. I have no experience of attempting this myself. Perhaps others do and can comment. See
The US has the most favourable dividend withholding tax arrangement for investors, Again, HL “However, if you have provided us with a valid W-8BEN form, we will claim reduced withholding tax payments from US or Canadian stocks, whenever possible.”
The UK also has a favourable regime as it charges 0% withholding tax on dividends. Germany, France, etc do seem to operate less investor-friendly dividend withholding tax regimes.
Remember that withholding taxes are also being charged to ETF providers. So if you hold EXS1 iShares Core DAX you are effectively paying the German withholding taxes without any possibility of a tax reclaim or credit against UK tax. EXS1 has yield of just 0.80% whereas the gross yield of DAX is over 3%. Withholding tax contributes to the difference.
A UK investor can take a credit of 15% against the German tax of 26.375%. For a UK higher rate taxpayer that would leave a dividend tax on 100 euros of 26.375 - 15 + 32.5 = 43.875. After completing paperwork with German tax authorities it could be reduced to 32.5. A basic rate taxpayer would end up paying 26.375 since there would be no additional UK tax, or 15% after make a reclaim.