Those are countries with _some sort_ of skilled immigrant tax relief scheme. I doubt many are even in the same ballpark as the Portuguese one. The Irish scheme, at least, is _far_ more limited; it applies only to existing employees of foreign companies (ie people who transfer), is time limited, and applies only to earned income over 100k (30% of which is disregarded for income tax, though not social taxes). So, for someone earning 200k, the tax on the upper 100k would be at 40% instead of 52% (normally composed of 40% income tax + 12% social taxes, 0.3*40=12, 52-12=40). That’s worlds away from a 20% flat tax, on all income, forever.