The answer to the cost to install a generator in Illinois is that it can vary widely depending on several factors. Typically, the cost to install a whole-home backup generator in Illinois can range from $5,000 to $15,000 or more, with the average being around $10,000.
The main factors that influence the cost include the size and type of generator, the complexity of the electrical work required, the accessibility of the installation site, and any necessary permits or inspections. Larger generators and more complex installations will be on the higher end of the range. It's also important to factor in ongoing maintenance and fuel costs for the generator.