This article provides a quality check of the degrowth movement's proposal of local currencies as tools for advancing socially equitable and ecologically sustainable degrowth. The article draws comprehensively upon mainly English-language academic research about four widespread local currency types – LETS, time banks, HOUR currencies, and convertible local currencies (CLCs) – to assess their performance with respect to four degrowth-related criteria: community-building, advancement of alternative values in economic exchange, facilitation of alternative livelihoods, and eco-localization. LETS have been found to support alternative livelihoods under quite uncommon conditions, and contribute indirectly to eco-localization by moderately facilitating informal resale, repair, and sharing of commercially produced goods, although their burdensome management and confinement to small memberships limit their usefulness. Time banks help expand social networks, and are best at reaching the socially excluded. However, they are confined to unskilled personal services and dependent on grant funding. HOUR currencies do not stand out with regard to any criteria, but may have a minor capacity to promote local purchasing. CLCs are best at attracting local businesses, but no significant evidence of their said capacity to localize supply chains has surfaced as yet, and their business-friendly design works to the detriment of other criteria. In sum, existing research provides a very weak basis for advocating local currencies as tools for purposive degrowth. Local currencies are here categorized as two utopian socialist approaches: the behind-society’s-back variety of LETS and HOUR currencies, and the appeal-to-elites variety of time banks and CLCs. Marx and Engels's critiques of these approaches remain valid: successful monetary systems require resources that are not available behind society's back, notably the power to levy taxes and designate by which means they can be paid. Local currencies that appeal for elite support – without mass popular backing – have shaken off most radical connotations, and are vulnerable to changing policy agendas. Given the present historical conjuncture of popular outrage against the banking sector, this paper argues that the degrowth movement would improve its chances of contributing to purposive degrowth by prioritizing government-centred ecological reform of the monetary system over local currencies.