New York’s mayor-elect, Zohran Mamdani, campaigned on a promise to raise the city’s income tax on its richest residents from 3.9% to 5.9%…. It set off a chorus of warnings about the tax flight of the city’s wealthiest residents…. I research whether high earners actually move when their taxes go up…. The first fact is simple: Millionaires have low migration rates. Mobility in America is highest among people who are still searching for their economic place in life. Workers who earn the lowest wages move across state lines at relatively high rates, about 4.5% per year, often in search of more affordable housing. People making $1 million-plus a year move only half as often: Just 2.4% of them pack up each year. When millionaires do move, it rarely appears to be for tax reasons. For example, Florida is the top destination for New York movers in general. But among the richest 1% of New Yorkers, the top destination is Connecticut, followed by New Jersey and California, all three of which levy a millionaire tax.