At least compared to the rest of the West:
The top U.S. marginal tax rate — 35 percent — is low by the standards of developed countries. It's about 51 percent in Britain, 47.5 percent in Germany, and 40 percent in France. Until recently, Denmark's highest tax rate was a whopping 63 percent, but that's been recently cut down to about 51 percent — good news for billionaires like Lego tycoon Kjeld Kirk Kristiansen.
Not all rich countries tax heavily however. At 29 percent, Canada's top rate is actually lower than the United States. But what about the dynamic growing superpowers of the developing world? Things are a little easier for the Learjet set there. Brazil's top income tax rate is 27.5 percent and India's is 30.9 percent. China's is a relatively high 45 percent; however tax evasion is pervasive, so it's unlikely that most of the country's 115 billionaires actually pay that much.