The origins of prepositional phrase structure in Finnic languages shows little evidence of being contact-induced. However, whether language contact has influenced the structure at a later stage is debatable. The current paper provides new findings on the topic of contact-induced change by comparing the distribution of prepositions in Estonian dialects with the respective contact languages. The purpose is to determine whether the usage frequency of prepositions is higher in areas mainly in contact with prepositional Indo-European languages. The topic is approached from a corpus-based, frequency-driven viewpoint. The results show a small, gradual decrease in the use of prepositions from the northeastern to the western dialect areas. Thus, the uneven but regular distribution of prepositions in Estonian dialects cannot be explained with language contact. This evidence supports the general understanding that adpositions are an unlikely class to be influenced by contact.