If there is a time for everything, what is the time for tipping? When do people tip more? … or less? This chapter seeks to answer these questions by reviewing research on temporal differences in tipping. It starts with time-of-day effects and moves on to consider day-of-week effects, monthly/seasonal effects, and holiday effects. The main takeaways are that temporal differences in tipping do exist, but they are rarely large or consistent across service contexts and they have few practical implications that are not already well known.