Thermally activated polarization (TAP) and thermally activated depolarization (TAD) effects resulting from impurity‐vacancy dipole reorientation occur in Mg‐doped and undoped lithium fluoride in the temperature region 200–250°K. These polarizations appear related radiation‐induced thermally activated depolarization (RITAD) effect in the same samples. We measure reorientation rate activation parameters of activation energyEa=0.44±0.03 eV and preexponential factorW0=108.5±1.5sec−1for simple divalent impurity‐vacancy dipole reorientation. Conversion to a second polarization phenomenon, stabilizing atEa=0.86±0.03 eV andW0=1019±1.5sec−1is observed during annealing for several days at room temperature. This seems to be caused by aggregation into dipolar complexes for which the activation energy becomes significantly temperature dependent.