Seasonal occurrence of cetaceans along the Washington coast has been difficult to characterize due to decreased daylight and inclement weather conditions resulting in a lack of survey effort throughout the year.  Acoustic recorders were deployed at four sites spanning the Washington coast from April 2008 to August 2013 to record and detect sound-producing cetaceans.  The most frequently detected cetaceans were gray whales (Eschrictius robustus), humpback whales (Megaptera novaengliae), sperm whales (Physeter macrocephalus), and killer whales (Orcinus orca). Unlike previous surveys, year-round acoustic monitoring indicates that migratory species such as gray, humpback and sperm whales use parts of the Washington coast throughout the year.  This information is essential for estimating the potential for human interactions such as entanglement or ship strikes with these species.   The seasonal occurrence of the four species monitored was variable between the four sites, even amongst those sites that were closest in proximity.  These results indicate that caution must be used when extrapolating the results of site specific monitoring to a larger scale. Utilizing a loose network of passive acoustic recorders, we were able to characterize the spatial and seasonal occurrence of cetaceans on the Washington coast during times of the year in which aerial and ship surveys are not feasible.  Additionally, we provide a baseline for monitoring yearly shifts in occurrence due to changing population demographics, oceanographic conditions, or anthropogenic inputs.