<p>Despite consistent evidence of the cardioprotective benefits of reduced-sodium salt, it remains an underutilised intervention. Understanding how reduced-sodium salt is perceived is required to scale-up its use. This review summarises end user and healthcare professional knowledge, attitudes, and behaviours about reduced-sodium salt. We systematically searched four databases (inception to February 2024) and identified studies reporting knowledge, attitudes and behaviours towards reduced-sodium salt. Twenty-nine studies from 11 countries were included, 18 of which were intervention studies involving reduced-sodium salt and 11 were descriptive studies examining perceptions among the general community and healthcare professionals. Among intervention studies, there was high overall acceptability but mixed findings on taste. Outcomes related to use or willingness to use were mostly positive especially following cost-subsidisation. Among descriptive studies, there was low awareness (ranging from 0–32%) and reported use (10–16%) of reduced-sodium salt among the general community. Barriers to use included low availability and higher costs compared to regular salt. Awareness was higher among healthcare professionals (71%). Overall, most studies found high acceptability and willingness to use following exposure to reduced-sodium salt, despite some detecting taste differences. Greater awareness coupled with strategies to improve availability and affordability are important to scale-up the use of reduced-sodium salt.</p>