Compared to the other cities in Illinois and cities in all other U.S. states, how safe is Vernon Hills, IL? From the gauges displayed above, you will notice that Vernon Hills, IL has been ranked safer than 51% of other cities in the state of Illinois. In addition, Vernon Hills, IL is safer than 71% of cities in the entire United States. To achieve these results, all Illinois and United States cities were analyzed to determine how many locations had a lower crime rate than Vernon Hills, IL. By studying this data, it was possible to determine that Vernon Hills, IL is above average in safety when compared with other United States cities.