There is increasing provision of welfare benefits advice in primary care (WBAPC). This reflects the present government's recognition of the association between socioeconomic and health inequalities. However, the assumption that increasing an individual's income will improve their health is not based on clear evidence. This paper reviews the relevant evidence, using four categories of pathways from poverty to ill-health: individual material; environmental material; individual psychological; environmental psychological. A description is offered of the scope and limits of WBAPC as a health intervention: one that primarily offers relief from psychological stress for service users, who tend to be middle-aged or older and suffering from chronic disease or disability. WBAPC may also make a small contribution to the physical health of individuals and to the social capital of communities. Thus to define the scope of WBAPC does not diminish its value to its beneficiaries, who carry a significant burden of both poverty and illness, nor does it in any way weaken the ethical argument for public policy to seek to reduce inequalities, and for primary care to play its part in that.