Plug-in Electric Vehicles (PEVs) will be an integral part of smart grids in the near future. This paper studies the impacts of different PEV battery charging profiles on the performance of smart grid distribution systems. PEVs are already growing in popularity as a low emission mode of transport versus conventional petroleum based vehicles. Utilities are becoming concerned about the potential stresses and overloads that may occur with multiple domestic PEV charging activity. Smart grids will play an important role in PEV operation because the battery chargers can be coordinated by the utility and harnessed for storing surplus grid energy and reused to support the grid during peak times. Therefore, an analysis is performed for a smart grid distribution system to demonstrate the impacts of different PEV charging scenarios. The paper compares charging rates (e.g., slow, medium and fast charging), PEV penetration levels as well as different charging periods over a 24 hour period considering existing system load profiles, and evaluates the overall performance of the distribution system. The impact on system load profile, total losses, transformer loading and voltage profile is examined.