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Migratory connectivity describes the linkage between breeding and non-breeding sites, having major ecological implications in birds: one season influence the success of an individual or a population in the following season. Most studies on migratory connectivity have used large-scale approaches, often considering regional populations, but fine-scale studies are also necessary to understand colony connectivity. The lesser kestrel Falco naumanni, an insectivorous migratory raptor which form colonies during the breeding period, was considered to have strong connectivity based on regional populations. However, no small scale studies on migratory connectivity have been conducted. Therefore, we GPS-tracked 40 adult lesser kestrels from 15 different Spanish breeding colonies, estimating the overlap index between home ranges and the distance between their centroids. It was found that lesser kestrels from the same breeding colony placed their non-breeding areas at 347 ± 281 km (mean ± standard deviation) away from each other (range = 23-990), and their home ranges overlapped by 38.4 ± 23.6%. No differences between intra-colony and inter-colony metrics were found, which suggests that lesser kestrels from the same breeding cluster do not overwinter together, but they spread out and mixed independently of the colony belonging throughout the non-breeding range of the species. Ultimately, this study highlights the importance of performing connectivity studies using fine-scale approaches. Funding for lesser kestrels tagging was provided by Iberdrola España Foundation (MIGRA program of SEO/BirdLife), GREFA (supported by Ministerio para la Transición Ecológica y Reto Demográfico, Junta de Castilla-La Mancha and SEITT, s.a.), Córdoba Zoo, Alcalá de Henares Municipality, and Global Nature Foundation within the LIFE Project “Steppe Farming” (LIFE15417NAT/ES/000734). Lina Lopez-Ricaurte has received financial support through the “La Caixa” INPhINIT Fellowship Grant for Doctoral studies at Spanish Research Centres of Excellence, “La Caixa” Banking Foundation, Barcelona, Spain. In Andalucia tags were funded by “KESTRELS MOVE” project (ref: CGL2016 79249 P) (AEI/FEDER, UE). At the time of analyses and writing, this study was supported by projects MERCURIO (ref: PID2020-421115793GB) (AEI/FEDER,UE) and SUMHAL (European Regional Development Fund4 (ref: LIFEWATCH-2019-09-CSIC-13) (MICINN, POPE 2014-2020). Logistic and technical support was provided by ICTS-RBD.