Adult tissues maintain function and architecture through robust homeostatic mechanisms mediated by self‐renewing cells capable of generating all resident cell types. However, severe injury can challenge the regeneration potential of such a stem/progenitor compartment. Indeed, upon injury adult tissues can exhibit massive cellular plasticity in order to achieve proper tissue regeneration, circumventing an impaired stem/progenitor compartment. Several examples of such plasticity have been reported in both rapidly and slowly self‐renewing organs and follow conserved mechanisms. Upon loss of the cellular compartment responsible for maintaining homeostasis, quiescent or slowly proliferating stem/progenitor cells can acquire high proliferation potential and turn into active stem cells, or, alternatively, mature cells can de‐differentiate into stem‐like cells or re‐enter the cell cycle to compensate for the tissue loss. This extensive cellular plasticity acts as a key mechanism to respond to multiple stimuli in a context‐dependent manner, enabling tissue regeneration in a robust fashion. In this review cellular plasticity in the adult liver and stomach will be examined, highlighting the diverse cell populations capable of repairing the damaged tissue.