Tourism is a major global industry and air travel is an increasingly vital component of international tourism. This paper examines the neglected relationship between tourism and aviation with regard to global environmental impacts, including energy use and greenhouse gas emissions. Based on visitor arrival data collected by Statistics New Zealand, it estimates a total energy use of 27.8 PJ resulting from international passenger air travel to New Zealand, which would increase national energy use by 6% if international air travel were included in national inventories. This energy use translates into additional carbon dioxide emissions of 1.9 million tonnes. These estimates are discussed in terms of a tourist's 'energy bill', national and international climate change policies, and with regard to the concept of sustainable tourism development.