The European Geostationary Navigation Overlay Service (EGNOS) is the first pan-European satellite navigation system. It is the Europe's regional satellite-based augmentation system (SBAS) deployed to provide safety of life navigation services to aviation, maritime and land-based users. EGNOS achieves its aim by transmitting a signal containing information on the reliability and accuracy of the positioning signals sent out by GPS.

EGNOS is a joint project of ESA, the European Commission and Eurocontrol, the European Organisation for the Safety of Air Navigation.