In Illinois, there is no State Electrical License leaving the licensing to each individual city and town. These cities and towns depend on municipal electrical licenses to help maintain a certain degree of electrical competence.
There are municipalities that issue electrical contractor licenses based on Illinois state guidelines. Please visit each city or town's website in Illinois to verify whether your license is accepted in their municipalities.
Some municipalities do accept other municipalities licenses but you should always consult with a the municipality you are looking to work in to make sure you are able to use your current license. If in doubt check it out.
The following link is from IAEI and has an extended listing per county.
Hope this helps!
P.S. Check out our website for a list of popular study materials for your licensing exam.