New York State, like most states, exempts religious, charitable, and educational institutions, including hospitals from any property tax. This exemption is required under the New York State Constitution. Without the exemption, the fourteen institutions with property worth more than $500 million would have paid up to $1.5 billion this year. Amending the State Constitution is a difficult and lengthy process, but a number of other cities with large amounts of charitable property and similar limits on taxing it, make up some of the resulting lost tax revenue by encouraging their universities, hospitals, and charitable institutions to make voluntary payments based loosely on what they would have owed under the property tax. This brief discusses the rationale for continuing the charitable exemption in its present form and presents a simple model of how agreements between New York City and the universities and hospitals could be put in place to generate hundreds of millions of dollars in revenue for the city.