According to data from the US BLS, the unemployment rate of Connecticut was 4.4% (sa) in June, 2017. Among all Connecticut counties, these 3 were among those with high unemployment rates (nsa): Windham (5%), New Haven (4.9%), and Hartford (4.6%).

On the hand, the following three counties were among those with low unemployment rates (nsa): Tolland (4%), Middlesex (4%), and Litchfield (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.