The answer to 'how much does air filter cost in Illinois' is that the cost of an air filter can vary significantly depending on factors like the size, type, and brand. Typically, basic air filters for residential HVAC systems in Illinois range from $5 to $30 per filter. The higher-end filters with features like better filtration or longer lifespan can cost $50 or more.
The cost is influenced by the specific needs of your HVAC system, the efficiency rating you're looking for, and whether you need a custom size. It's best to get quotes from local HVAC companies or suppliers to understand the exact pricing in your area.