The COVID-19 pandemic and social distancing measures caused widespread social and economic disruptions, resulting in spikes in unemployment and financial instability, along with drastic changes to people's ability to feel socially connected. These changes could have implications on people’s sex lives as external stressors, like those introduced amidst the COVID-19 pandemic, are risk factors for depressive symptoms, which are associated with lower levels of sexual desire. The current research (N = 4,993) examined whether external stressors brought on by COVID-19 were associated with sexual desire among people in relationships (Studies 1-2), and whether this association was, in part, due to reports of depressive symptoms (Study 2). In the period immediately following the onset of the pandemic, more financial concern (Study 1) and worry (Study 2) were associated with higher sexual desire, while other factors, like stress (Studies 1-2), were associated with lower desire. We also followed a subset of participants every two weeks during the initial stages of the pandemic and at times when people reported greater stress, loneliness, financial strain, or worry than their average, they reported greater depressive symptoms, which, was in turn, associated with lower sexual desire. Results suggest that the social isolation and stress resulting from the COVID-19 pandemic has mixed associations with sexual desire at the onset of the pandemic. But over time, when people report heightened COVID-related stressors, like stress and loneliness, they tend to report lower sexual desire for their partner, in part because these stressors are associated with more depressive symptoms.