Contemporary academic literature has controversial opinions about selflessness of motives of volunteers. Some authors state that volunteers are primarily motivated either by altruistic causes or egoistic factors; others declare the impossibility of the existence of pure altruists or egoists in the activity. Part of scholars report on the extreme importance of age regarding volunteers’ motives. Conducted studies mostly consider volunteers with people. Papers investigating motives of volunteers with homeless animals are limited. A still unsolved question is whether it is reasonable to apply received results from those who volunteer with people to volunteers with non-human recipients. In the paper, we investigate the particularities and structures of motives among volunteers with diverse ages and recipients (N=220), utilizing VFI (Volunteer Function Inventory). The research sample consisted of volunteers serving people and/or homeless animals. It has been found that volunteers are mostly motivated by values, understanding, and enhancement functions. The social, career and protective functions were not common among the volunteers. Younger volunteers tend to be more multi-motivated and actuated by egoistic factors. Starting at age 25, the older the volunteer was, the more likely their motives were selfless and distinct. Studies such as ours can be valuable in recruitment and retention of volunteers according to their needs and motives. The obtained data can be used by organizations working with differently aged volunteers and diverse recipients of assistance (e.g., people, animals).