There are several factors that determine the cost of radio advertising, including the popularity of the station, time of day, and length of the commercial. Generally, advertisers pay £2 per 1000 listeners, with morning and evening rush hours being the most expensive. This document provides an example rate of £2910+VAT for a 30-second commercial aired 80 times over 1 week, reaching over 400,000 listeners on KEY 103 and MAGIC. Choosing a station whose audience matches the target demographic is important to effectively reach potential customers.