The transition to a circular economy requires that consumers take responsibility for both the acquisition and disposal of what they consume. In Europe and around the world, there has for a long time been a focus on reducing and recycling waste, including from households. This implies a responsibility for households to source-separate their waste and take the recyclable fractions to designated containers or collection points, with the dual purpose of reducing landfills and reusing products and materials. However, for the latter to work, and for the economy to become truly circular, consumers must buy used products or products with recycled materials (i.e., circular products). Some consumers reject circular products, assuming they are of lower quality, while others value their environmental friendliness. In this study, we test the hypotheses that (a) the more consumers recycle, the more inclined they are to also buy circular products, and vice versa, and (b) that this behavioral spillover is mediated through strengthening the goal of waste reduction. These hypotheses are tested in a cross-lagged panel structural equation model by means of a two-wave online panel survey in Denmark (Copenhagen) and Portugal (Lisbon) (n ≈ 500 in wave 1 in each country). In both countries, we find a significant and positive cross-lagged effect from recycling to buying circular products, and in Portugal also the other way round. These “spillover” effects are mediated by commitment to and perceived progress toward the goals of waste reduction and saving resources – in Denmark primarily by goal commitment and in Portugal primarily by perceived goal progress. This suggests that communications to engage consumers in the circular economy should emphasize the logical connection between recycling and buying circular products, and in particular the superordinate waste and conservation goals to which both contribute.