A general overview of the cost of living index for Arnold, MO is displayed above. In Arnold, MO, the overall cost of living index is 94, which is 4% higher than the Missouri average and 6% lower than the U.S. average. The following categories are used to calculate the overall cost of living index: goods/services (33%), housing (30%), groceries (13%), utilities (10%), transportation (9%) and health care (5%). From the list, it is clear that the categories of goods/services and housing are responsible for the largest portions of the overall cost of living index. As a general rule, everyday goods and services provide an accurate measure of the general cost of goods in any given city. In the case of Arnold, MO, the city's goods and services are 2% lower than the Missouri average and 9% lower than the U.S. average.