Compared to the other cities in Massachusetts and cities in all other U.S. states, how safe is Nantucket, MA? From the gauges displayed above, you will notice that Nantucket, MA has been ranked safer than 27% of other cities in the state of Massachusetts. In addition, Nantucket, MA is safer than 39% of cities in the entire United States. To achieve these results, all Massachusetts and United States cities were analyzed to determine how many locations had a lower crime rate than Nantucket, MA. By studying this data, it was possible to determine that Nantucket, MA is below average in safety when compared with other United States cities.