Measures of loneliness are usually individualistically worded and commonly refer to loneliness with respect to relationships with at most a group of friends or ambiguous “people”. In light of the current discussion of a collapse in community and an epidemic of loneliness (Office of the Surgeon General, 2023; Putnam, 2020a, 2020b), it is vital to develop a new and reliable way to measure collective loneliness. To this end, we started with scoping review of collective loneliness and related concepts to generate the items. The preliminary dimensions of the scale were 1) levels: small groups, community, society, and world, and 2) themes: perceived situation, direct loneliness, connectedness, otheredness, isolation, neededness, and need-fulfillment. Based on past literature and feedback from the qualitative interviews, 131 items were generated. The two group interviews and ten individual interviews additionally aided in evaluating the items (n = 15). The items were further evaluated in a pre-test (n = 34) to assess content and face validity, difficulty, ambiguity, and social desirability, and a pilot (n = 48) to preliminarily assess psychometric properties. These evaluations together with an expert review were used to reduce the scale to twelve items. Then the factor structure of the reduced scale was assessed in a sample of adults (n = 853). Finally, measurement invariance was tested among a sample of adolescents (n = 156) and psychometric properties assessed. Our results suggest that our new Collective Loneliness Scale is a valid scale that measures loneliness concerning collectives to complement current individualistic loneliness scales.