Several studies have shown that (i) grandparental support varies according to gender and lineage, and (ii) differences in family relationships tend to exist between lower and higher socioeconomic status (SES). However, there is a lack of studies examining whether grandparents provide more support to grandchildren from lower- or higher-SES families in contemporary affluent societies, and whether this differs between maternal and paternal grandmothers and grandfathers. We used population-based data from Germany and applied generalized ordered logit models to examine how grandparental childcare and financial support vary with the SES of grandchildren’s families, measured by parental education and household income. It was detected that grandparents provided frequent childcare help more often to grandchildren whose parents had higher levels of education and income. Specifically, frequent childcare help from maternal grandmothers increased as parental education levels rose. Additionally, paternal grandparents provided more financial support to families in the medium, high, and highest income classes compared to those in the lowest income class. These findings are more consistent with an accumulation pattern than a compensation pattern, suggesting that grandparental support may contribute to the persistence of socioeconomic inequalities between families.