The number and size of marine protected areas (MPAs), implemented globally to protect coastal habitats from human pressures, is growing annually. Commercial and recreational fishing are a commonly recognised stressor in coastal habitats, but the impact of sound pollution is largely overlooked in MPA design. Coastal habitats are taxonomically diverse, and this diversity is commonly represented in the soundscape, with many coastal species relying on effective communication for vital life functions, including breeding, prey selection, and predator avoidance. Sound pollution can mask communication and cause behavioural and physiological effects. More research is required to understand the role of sound in marine ecosystems, including which species actively produce sound. In the interim, the effects of sound pollution on those species which have been studied, and the relative ease with which sound pollution can be mitigated, strongly supports addressing this stressor in the design and management of existing and future MPAs.