Although the range of mobile messaging services available has become richer and more diverse during the 2000s, ‘messaging’ is still overwhelmingly dominated by a single, 15-year old service: SMS. Blended messaging refers to platforms and technologies that allow operators to evolve mobile messaging by presenting users with a single environment for all messaging - the handset and network transparently decide which technologies should be used to transport the message, according to its payload and the properties of its destination. We examine what blended messaging means, how it has developed so far, and analyse the pros and cons of blended messaging from the perspective of operators and end-users. We also consider the likely role of blended messaging in the development of mobile messaging during the next few years.