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An overview of the electromagnetic (EM) physics of the Geant4 toolkit is presented. Two sets of EM models are available: the" Standard" initially focused on high energy physics (HEP) while the" Low-energy" was developed for medical, space and other applications. The" Standard" models provide a faster computation but are less accurate for keV energies, the" Low-energy" models are more CPU time consuming. A common interface to EM physics models has been developed allowing a natural combination of ultra-relativistic, relativistic and low-energy models for the same run providing both precision and CPU performance. Due to this migration additional capabilities become available. The new developments include relativistic models for bremsstrahlung and e+ e-pair production, models of multiple and single scattering, hadron/ion ionization, microdosimetry for very low energies and also improvements in existing Geant4 models. In parallel, validation suites and benchmarks have been intensively developed.