Due to their high item difficulties and excellent psychometric properties, construction-based figural matrices tasks are of particular interest when it comes to high-stakes testing. An important prerequisite is that test preparation - which is likely to occur in this context - does not impair test fairness or item properties. The goal of this study was to provide initial evidence concerning the influence of test preparation. We administered test items to a sample of N = 882 participants divided into two groups, but only one group was given information about the rules employed in the test items. The probability of solving the items was significantly higher in the test preparation group than in the control group (M = 0.61, SD = 0.19 vs. M = 0.41, SD = 0.25; t(54) = 3.42, p = .001; d = .92). Nevertheless, a multigroup confirmatory factor analysis, as well as a differential item functioning analysis, indicated no differences between the item properties in the two groups. The results suggest that construction-based figural matrices are suitable in the context of high-stakes testing when all participants are provided with test preparation material so that test fairness is ensured.