Individuals have the option of remembering delayed intentions by storing them in internal memory or offloading them to an external store such as a diary or smartphone alert. How do we route intentions to the appropriate store, and what are the consequences of this? We report three experiments (two preregistered) investigating the role of value. In Experiment 1, participants preferentially offloaded high-value intentions to the external environment. This improved memory for both high- and low-value content. Experiment 2 replicated the low-value memory enhancement even when only high-value intentions were offloaded. This provides evidence for a cognitive spillover effect: When high-value content is offloaded, internal memory becomes reallocated to low-value content instead. Experiment 3 confirmed a theoretical prediction of this account: participants had superior memory for low- than high-value content when the external store was removed. These results imply that value-based offloading can lead to a cognitive spillover effect from high- to low-value content, similar to the automatic allocation of “spare” capacity that has been proposed in the domain of visual attention. Individuals prioritize high-value information for external memory; consequently, they can be left with predominantly low-value information if it fails.