But Urs is a US tax resident for life now, US doesn’t let you become non-resident. So he will continue to owe capital gains in the US and if he becomes NZ resid

But Urs is a US tax resident for life now, US doesn’t let you become non-resident. So he will continue to owe capital gains in the US and if he becomes NZ resident that doesn’t change. But he will then owe NZs higher tax rates on his regular income and other things too (like foreign financial arrangements which can get messy). Edit: IANAtaxL but NZ does have a pretty sweet deal where new residents get to not pay tax on overseas income for four years. So Urs could come in for four years. Then if he maintains a permanent home in the US that is always available to him (not rented) a tax expert might argue he is dual resident and under the dual tax agreement would tie break to the US so doesn’t owe tax in NZ on his US income, which would be all of his income. So this is probably what he would do. It’s a pretty sweet deal, I don’t think it’s fair you basically don’t pay tax to NZ under that arrangement if your income is overseas and you can afford to leave a house unrented.