ABSTRACT In North America's Pacific Northwest, archaeologists have extensively researched coastal fish weirs—one of several types of mass fish capture technologies used by precontact peoples—and their role in the development of delayed return economies and implications for social organization. Fish weirs, however, are typically situated in areas that are susceptible to a range of geomorphic and anthropogenic factors that affect their preservation and visibility. Given the importance of these capture facilities to understanding the histories of coastal peoples, a better understanding of these factors, and how they affect the archaeological record, is needed. Using the recently augmented coastal fish weir record in Washington State as a case study, we explore these factors by compiling an expanded database of 22 sites and 36 radiocarbon dates and systematically consider how coastal geomorphological processes operating along the Northwest Coast affect the age and distribution of fish weirs. Through this analysis, we argue that regional patterns in cultural use and taphonomy of the construction of fish weirs, as well as human responses to coastal dynamism, must be considered through the lens of geomorphic and anthropogenic factors that affect the coastal margin on a local and regional scale.