Given the proliferation of novel digital marketing channels, decision makers need to understand how a mature channel like email fits into the marketing mix. This forecast provides guidance on how email marketing spending will evolve over the next five years and how that growth will be distributed across three vendor types and 12 industry verticals. We also include forecasts of email users and smartphone email users by age as well as email volume by age and commercial volume. The report contains historical data going back to 2005 and a five-year forecast.