Proactive identification of chemicals with skin sensitizing properties is a key toxicological endpoint within chemical safety assessment. In order to meet recent legislations and increase animal welfare, considerable efforts have been made to develop non-animal approaches to replace current animal testing. Genomic Allergen Rapid Detection (GARD™) is a state-of-the-art technology platform, the most advanced application of which is the assay for assessment of skin sensitizing chemicals, GARD™skin. The methodology is based on a dendritic cell (DC)-like cell line, thus mimicking the mechanistic events leading to initiation and modulation of downstream immunological responses. Induced transcriptional changes are measured following exposure to test chemicals, providing a detailed evaluation of cell activation. These changes are associated with the immunological decision-making role of DCs in vivo and include among other phenotypic modifications, up-regulation of co-stimulatory molecules, induction of cellular and oxidative stress pathways and xenobiotic responses. Here, results from an inter-laboratory ring trial of GARD™skin, conducted in compliance with OECD guidance documents and comprising a blinded chemical test set of 28 chemicals, are summarized. The assay was found to be transferable to naïve laboratories, with an inter-laboratory reproducibility of 92.0%. The within-laboratory reproducibility ranged between 82.1-88.9%, while the cumulated predictive accuracy across the three laboratories was 93.8%. Based on these and previously published data, it is concluded that GARD™skin is a robust and reliable method for the identification of skin sensitizing chemicals and suitable for use as a stand-alone assay. These data form the basis for the regulatory validation of GARD™skin.