People associate numbers and horizontal space. This association has been demonstrated by the so-called SNARC (Spatial-Numerical Association of Response Codes)-effect, with Western participants responding faster to larger numbers with their right hand and vice versa for smaller numbers. SNARC-like effects have also been reported for preschoolers. However, it remains unclear whether children's SNARC-effects are exclusively based on number or whether nonnumerical factors such as surface area can also play a role. To address this question, we asked children to compare quantities in a nonsymbolic number comparison task. On half of the trials, the larger set took up more total surface area (congruent trials), and on the other half, the smaller number had more surface area (incongruent trials). We obtained a significant interaction of SNARC-like effects and congruency. SNARC-effects were only observed for congruent trials, demonstrating that preschoolers' spatial-numerical associations can be affected by nonnumerical magnitude.