The cost of a central air conditioning system can vary widely depending on several factors, including the size and efficiency of the unit, the complexity of the installation, and your geographic location. On average, for a typical residential central AC system, including installation, you can expect to pay anywhere from $3,000 to $7,000 or more. However, high-efficiency or larger systems, as well as those with advanced features, can cost significantly more. It's essential to obtain multiple quotes from reputable HVAC contractors to get an accurate estimate for your specific needs and location. Additionally, local incentives, rebates, and financing options may impact the overall cost of your new AC system.