Countries and cities around the world have resorted to unprecedented mobility restrictions to combat Covid-19 transmission. Here we exploit a natural experiment whereby Colombian cities implemented varied lockdown policies based on ID number and gender to analyse the impact of these policies on urban mobility. Using mobile phone data, we find that the severity of local lockdown rules, measured in the number of days citizens are allowed to go out, does not correlate with mobility reduction. Instead, we find that larger, wealthier cities with a more formalized and complex industrial structure experienced greater reductions in mobility. Commuters are more likely to stay home when their work is located in wealthy or commercially/industrially formalized neighbourhoods. Hence, our 1 arXiv:2010.14630v1 [physics.soc-ph] 27 Oct 2020 results indicate that cities’ employment characteristics and work-from-home capabilities are the primary determinants of mobility reduction.