Recently, research in second language acquisition has seen an increased attention on low-educated low-literate (LESLLA) learners. However, few of the existing instruments to measure L2 proficiency have been validated for use with this population. In this paper, we examine how adult L2 learners with diverging educational backgrounds perform on and engage with a L2 receptive skills test that was specifically developed with LESLLA learners in mind. To gauge test perception and strategies, 48 less- and highly-educated L2 learners participated in cognitive interviews. Additionally, a live test was administered to 616 adult L2 learners to assess the impact of educational background on L2 performance. Combining psychometric and interview data, this study not only provides initial validation of the test for a diverse group of adult L2 learners, but also offers insights into the test-taking experiences of LESLLA learners, addressing a long-neglected group in applied linguistics research.