According to the Tax Foundation, a Washington, DC-based research group, Westchester taxpayers write the largest property tax check in the country—yes the country: $8,404, or nearly five(!) times the national average of $1,854. Part of that is due to the value of the homes, but they are only three times the national average. It’s the tax rates, some of the highest in the state and nation. Nassau County is close at $8,306, Rockland is $7,798, Putnam is $6,917, and Suffolk is $6,842. Bergen County, New Jersey—just across the river—is $7,997, while Fairfield, Connecticut, is $6,051. Tax-wise, it’s cheaper to live in Greenwich than in Mamaroneck.