In and , concentration‐ and temperature‐dependent loss and storage effects are observed for excitation into the Eu+3 charge‐transfer states (CTS) and into certain Eu+35D states. It is shown that the losses and storage both occur from the CTS. They occur for 5D excitations only as a consequence of the 5D excitation having reached the CTS through thermally promoted crossovers. The losses and storage are both attributed to the Eu+3 CTS dissociating thermally into Eu+2 plus a free hole. The freed holes are stored in hole traps. If the holes are thermally or IR stimulated back to the Eu+2 centers and reform the Eu+3 CTS, the stored energy is retrieved as Eu+3 line emissions. If the extra electrons at the Eu+2 centers migrate through the Eu activators and recombine nonradiatively at the hole centers, the stored energy is lost.