Cross-border work is expanding in the EU, yet its labor-market effects on the cross-border workers themselves remain largely undocumented. Using linked Belgian administrative registers that identify cross-border spells in Luxembourg, we estimate the effects of cross-border employment on post-return labor-market outcomes through dynamic double machine learning. Returnees face a short-run employment penalty that fades with cross-border tenure and time since return. They are also more likely to receive Belgian unemployment benefits than comparable stayers, with higher daily benefit levels among recipients.