"Hospital" can refer to a physical place or more figuratively to the people associated with it. Such place-for-institution metonyms are common in everyday language, but there remain several open questions in the literature regarding how they are processed. The goal of the current eyetracking experiments was to investigate how metonyms are interpreted when they appear as sentence subjects in structures that are temporarily syntactically ambiguous versus unambiguous (e.g., "The hospital [that was] requested by the doctor…"). If comprehenders have a bias to interpret metonyms in subject position as agents (Fishbein & Harris, 2014), they should initially access the figurative (institutional) sense of the metonym. This interpretation is rendered incorrect at the disambiguating by-phrase, which should lead to reanalysis (i.e., garden-path effects). In Experiment 1, larger garden-path effects were observed for metonyms compared to inanimate control nouns that did not have a figurative sense. In Experiment 2, garden-path effects were equivalent for metonyms and animate sentence subjects. In addition, there was some evidence that readers exhibited initial difficulty at the verb (e.g., "requested") when it immediately followed the metonym compared to the inanimate control nouns in Experiment 1. Overall, the results suggest that the subject-as-agent heuristic is a powerful cue during sentence processing, which can prompt the comprehender to access a figurative interpretation of a metonym.