In recent years there has been a large increase in the number of e-cigarettes on the market, the majority of which are designed to resemble the appearance of a standard cigarette. These devices are generally claimed to deliver nicotine and tobacco flavour to the smoker without producing the combustion and pyrolysis products associated with lit cigarettes. Most e-cigarettes use a heating element to vaporize liquids contained within a separate attached cartridge and thereby enable the delivery of these vapours to the smoker. As a result, the way in which an e-cigarette produces and delivers substances to the consumer is totally different to conventional cigarettes and it may be anticipated that smoking regimes that have been developed for standard cigarettes may not provide the most suitable basis comparing yields from e-cigarettes. Owing to the very recent introduction of these products, little information is currently available into the effects of puff volume, puff duration and puff number on the yields of e-cigarettes. This present work is part of a programme intended to provide more data into the effects of smoking parameters on the yields of e-cigarettes. In this paper, results will be presented into the effect of puff number on the yields of total particulate matter, nicotine and water from a range of different commercially available e-cigarettes and these results will be compared with data from standard cigarettes.