Basic income is a social policy tool that raises as many positive as negative emotions. It is a controversial instrument but still discussed. This idea is raised especially in times of danger, when the social, health, or economic crisis may deprive citizens of their livelihood and wellbeing. The following article provides the definition and assumptions for basic income. Various modifications of guaranteed income occurring in the literature are indicated. The ideas of negative income tax, fixed grant, and then universal basic pension were presented. Differences in particular models were indicated and their advantages and disadvantages were discussed.