Tourette’s syndrome (TS) and obsessive-compulsive disorder (OCD) are neurodevelopmental disorders affecting ~0.6% of the total population. Although the full etiology of these disorders remains largely unknown, there are severe cases of TS and OCD known to be caused by a nonsense mutation in the Hdc gene coding for the enzyme responsible for histamine production with patients exhibiting lowered histamine levels. Both TS and OCD show strong social components where both stress and anxiety can facilitate as well as exacerbate symptoms, with an underlying cause remaining largely unknown. Therefore, we set out to investigate the functional roles for histamine in the early development of the bed nucleus of stria terminalis (BNST) – a brain region key in regulating anxiety and stress responses which is densely innervated by histaminergic afferents (Marquez-Gomez et al. 2023). Using whole-cell patch-clamp recordings and reconstructions we first devised a classification method of diverse neuron types within the BNST based on their electrophysiological and morphological characteristics during the second postnatal week. We found that BNST neurons can be classified during this stage of development using unbiased classification approaches. We next examined to what extent defined neuron types are responsive to superfusion of histamine. Results indicate that BNST neurons in general are modulated by histamine with electrophysiological parameters (e.g. spike amplitude) significantly altered, with some effects appearing neuronal subtype specific. Together, these results suggest that histamine is an active neuromodulator during early postnatal BNST development and suggest that dysregulated histamine could lead to aberrant regulation of its activity.