Conserving soil natural capital contributes to human welfare through its delivery of ecosystem services such as food security, water quality and climate regulation as well as providing insurance against future uncertainties, particularly climate change. However, individual farmers bear conservation costs, whereas particular services are public goods benefiting humanity generally. Consequently, farmers’ self-interested behaviour will not necessarily promote the optimal management of soil ecosystem services and underlying natural capital. Here we present a roadmap for evaluating the impacts of alternative farming practices that conserve soil ecosystem services, on farmers’ and societal welfare. The results of a Swedish case show that the value of conserving soil natural capital diverges depending on the level of decision-making: farmers or society. This is because public-good services have substantial societal value, and future flows of provisioning services have greater value to society than to current-generation farmers. We conclude that market outcomes are not likely to be generating optimal conservation of soil natural capital from society’s perspective. Innovative information systems and governance institutions are needed to guarantee the welfare of future generations.