Adolescents experiencing excessive anxiety are often under-identified in the school context, and consequently under-referred for in-school counselling or other mental health support. This is despite anxiety being the most prevalent mental health condition currently experienced by adolescents. The purpose of this study was to explore secondary teachers’ ability to recognise the need to refer adolescents with excessive anxiety symptoms. One hundred and fourteen secondary school teachers completed a questionnaire with five vignettes describing students experiencing various degrees of anxiety. Statistical analysis of the data involved use of the one-sample Wilcoxon test and Spearman’s rank non-parametric correlation coefficients. Results indicated that teachers recognised the need to refer adolescents with very severe anxiety symptoms. However, they were less likely to correctly identify and refer students with severe, moderate or mild anxiety symptoms. There was no statistically significant difference between male and female teachers’ decision to refer students for school counselling. These findings are an important step forward in understanding how teachers decide whether or not to refer anxious children for support, and in identifying areas for further training and professional development. Implications are discussed for future professional development for secondary school teachers.