According to data from the US BLS, the unemployment rate of New Hampshire was 2.6% (sa) in June, 2018. Among all New Hampshire counties, these 3 were among those with high unemployment rates (nsa): Cheshire (2.9%), Coos (2.9%), and Rockingham (2.9%).

On the hand, the following three counties were among those with low unemployment rates (nsa): Sullivan (2.2%), Merrimack (2.3%), and Grafton (2.4%).

The chart and table below shows the unemployment rate (nsa) for each county.

You can see similar information by state for the United States.