Airtrain from Brisbane Airport to the CBD (10% discount if you book and pay online)
(No discount is available for a single ticket when you travel from Central Station to the Airport though)
In only 20 minutes, you'll arrive at the heart of downtown Brisbane. This gives you stops at Bowen Hills, Fortitude Valley, Central Station, Roma Street and South Brisbane. So there's a station near your destination, no matter where that is.
The Airtrain stations at the Domestic and International Airports are located directly outside the terminals. Trains depart every 15 minutes to the city during peak times.
It's great to know that you can book Airtrain tickets in advance. Your ticket will be waiting when you arrive at the airport train station. This means you don't need to carry cash at the airport.
You can purchase both single and return tickets, with Airtrain offering you a discount on returns.
NOTE: Trains from the airport stop EARLY eg 7pm or 8pm. Check the timetables on the Airtrain web site. The only way to get from the airport to the CBD is by taxi or by charter bus. It is cheaper and quicker to get a few people together and share a taxi to the city.