Unlocking a pension is a term used to describe taking benefits from a pension. Usually in the context of taking pension benefits "early". For example when a person age 55 or over takes tax free cash from their pension. These benefits can be taken in the form of a lump sum or an income or both. However when the pension benefits are taken before the investors normal retirement age then they might be considered to be taken "early". Taking benefits early will reduce your future retirement income.