Greece is characterized by high seismotectonic activity. Extended Global Positioning System (GPS) reoccupation and continuous networks have been measured in order to study the crustal motion and deformation in this region, with particular interest in earthquake-related effects. In this article we present GPS-derived coseismic displacements in Greece, caused by the Ms 6.6 2001 Skyros and Ms 6.2 2003 Lefkada earthquakes. The coseismic effects are presented in terms of time series, displacement vectors, differences of velocity vectors, and changes of accumulated strain. Furthermore, we compare the GPS results with fault plane solutions and slip models of the corresponding earthquakes. We found discontinuous changes of position of about 70 mm for the island of Skyros, which can be attributed to the 2001 Skyros earthquake (Aegean Sea). A detailed displacement field was obtained for the 2003 Lefkada earthquake (Ionian Sea, Greece), which induced coseismic southwestward displacements of up to 72 mm. It is in agreement with the focal mechanism of the mainshock, which caused a dextral strike slip of maximum 34 cm on a northeast striking plane. The cumulative strain after the Lefkada earthquake indicates an increased seismic hazard for the island of Kefalonia, Ionian Sea, Greece. The 25 March 2007 Kefalonia earthquake was located in this region.