The investigation of immune senescence has uncovered many changes in B cell development, maintenance, and function with increasing age. However, most of these studies have focused on conventional B cell subsets in the spleen. The B‐1 cell subset is an essential arm of the innate immune system, which in general has been understudied in terms of immune senescence. Here, we review what is currently known about B cells during aging and go on to describe why B‐1 cell biology is an important component of the aging immune system in the context of diseases that most affect the aged population.