Tourism contributes substantially to municipal solid waste generation, yet the waste from tourism systematically remains hidden behind residential waste flows. As a result, municipal fees are set without precise information about waste producers’ contributions, causing budget imbalances and cross-subsidies between residential and economic activities. To estimate tourism’s contribution to mixed waste generation in an island destination, socio-demographic, economic and disposal-related factors are modelled using municipal panel data from 2004 to 2015 for Tenerife (Spain). In contrast to previous studies, a mixed demand-supply approach is adopted to estimate the contribution of main tourism activities to mixed waste generation, thus, differentiating between tourists and residents’ contributions. An auxiliary model is used to isolate employment levels in tourism activities attributable to residents’ consumption and to capture tourists’ and residents’ mobility on the island. Estimates show that main tourism activities generate 0.40 kg of mixed waste per tourist daily, while residential and economic sectors account for 1.19 kg per resident daily. This tourism contribution is significantly lower compared to other studies, as it captures tourism’s contribution to mixed waste generation, attributable only to tourists, following a mixed demand-supply approach. These results shift impacts from tourists to main tourism activities, which highlights the choices made by producers rather than the final customers and reinforces the producers extended responsibility principle. The implementation of a Pay-As-You-Throw tariff for mixed waste is discussed as a way of promoting waste prevention and recycling, as well as avoiding cross-subsidies among waste producers and, as a result, imbalances in municipal budgets.