The answer to 'how much does smoke detector cost in Illinois' is that smoke detector prices in Illinois can range from around $10 to $50 or more, depending on the type and features. Hardwired smoke detectors with battery backup and interconnected systems tend to be on the higher end of that range, while basic battery-powered models are usually on the lower end.
The specific cost of a smoke detector in Illinois can vary based on factors like the brand, quality, smart features, and whether it needs to be professionally installed. It's important to get quotes from local electricians or home improvement stores to get an accurate estimate for your specific needs and location.