According to data from the US BLS, the unemployment rate of Connecticut was 3.5% (sa) in July, 2019. Among all Connecticut counties, these 3 were among those with high unemployment rates (nsa): Windham (4.1%), Hartford (4%), and New Haven (4%).

On the hand, the following three counties were among those with low unemployment rates (nsa): Middlesex (3%), Tolland (3.3%), and Litchfield (3.3%).

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

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