This study examines the impact of social capital on accounting comparability. Empirical results show that firms headquartered in high social capital counties prepare financial statements that are more comparable with those of other firms. This indicates that managers of firms located in high social capital regions tend to design or adopt some accounting methods and systems that make their accounting output more comparable to that of other firms. The results also reveal that the positive impact of social capital on accounting comparability is more pronounced when the product market competition is low, indicating that managers in less competitive product markets have greater discretion in preparing these comparable statements. The instrumental variable approach reveals that the county-level social capital measure is exogenous to the accounting comparability model. The relationships still hold when the state-level Putman index is used to proxy for social capital. Robustness tests also strengthen the results.