To enable flexible and controlled research on personality, information processing, and interactions in socio-emotional contexts, the availability of highly controlled stimulus material, especially trait words and related attributes, is indispensable. Existing word databases contain mainly nouns and rating dimensions, and their role in studies within socio-emotional contexts are limited. This study aimed to create an English list of traits (ELoT), a database containing 500 trait adjectives rated by a large sample (n = 822, 57.42% female). The rating categories refer to the perceived valence associated with the traits and their social desirability and observability. Participants of different ages (18 to 65 years of age) and educational levels rated the words in an online survey. Both valence and social desirability ratings showed a bimodal distribution, indicating that most traits were rated either positive (respectively socially desirable) or negative (respectively socially undesirable), with fewer words rated as neutral. For observability, a bell-shaped distribution was found. Results indicated a strong association between valence and social desirability, whereas observability ratings were only moderately associated with the other ratings. Valence and social desirability ratings were not related to participants’ age or gender, but observability ratings were different for females and males, and for younger, middle-aged, and older participants. The ELoT is an extensive, freely available database of trait norms. The large sample and the balanced age and gender distributions allow to account for age- and gender-specific effects during stimulus selection.