We re-consider the impact that regulation of call termination on mobile phones has had on mobile
customers’ bills. Using a large panel covering 27 countries, we find that the ‘waterbed’ phenomenon,
initially observed until early 2006, becomes insignificant on average over the 10-year period, 2002–11.
We argue that this is related to the changing nature of the industry, whereby mobile-to-mobile traffic
now plays a much bigger role compared to fixed-to-mobile calls in earlier periods. Over the same
decade, we find no evidence that regulation caused a reduction in mobile operators’ profits and
investments.