The abstract concept of time is conceptualized as moving linearly across space, known as the mental timeline (MTL). The direction of our MTL is consistent with reading direction. English speakers, who read left to right, think of past on the left and future on the right; the reverse is true of Hebrew speakers, who read right to left. However, it is unknown whether familiarity with reading direction facilitates the development of the MTL or whether it develops prior to becoming familiar with a language's direction. This study examined the relationship between the development of the MTL and emergent literacy skills in English-speaking preschoolers and kindergartners. Results reveal a preference for spatially displaying time as moving horizontally from left to right in preschoolers, which is strengthened in kindergartners and predicted by emergent literacy skills. Results indicate that emergent literacy skills are related to the early development of the MTL, providing insight into the origins of the mental timeline.