Searches for highly ionising particles in ATLAS and CMS

The latest CMS and ATLAS searches for signatures with anomalously large ionization are presented. The findings are interpreted in terms of the production of new particles with a fractional or multiple value of the charge of the electron, the production of high mass stable charged particles, the presence of magnetic monopoles that lead to unusual ionization interactions with matter or the delayed effect of particles stopping in the detector volume. The HCSP signatures are also reinterpreted in the context of supersymmetric scenarios that predict stable or pseudo-stable charged particles in the final state.