Long-tailed Tit, Aegithalos caudatus, is a species of passerine bird in the long-tailed tit family found in cropland and woodland and forest ecosystems. It is a widespread resident across almost the whole of Europe. This species prefers deciduous and mixed woodland with a well-developed shrub layer, especially willows (Salix) and favouring edge habitats. It is also found in riverine woodland, scrub heathland with scattered trees, bushes and hedges in farmland and well-wooded suburban parks, cemeteries and gardens. In the Mediterranean it also uses maquis and open pine (Pinus) forest. Otherwise, avoids pure stands of conifers in west of range, but noted in open forests of spruce (Picea), fir (Abies), larch (Larix) and Siberian stone pine ( Pinus sibirica) in central Siberia.

Aegithalos caudatus has a breeding population size of 5830000-9390000 pairs and a breeding range size of 3390000 square kilometres in the EU27. The breeding population trend in the EU27 is Increasing in the short term and Increasing in the long term.

The EU population status of Aegithalos caudatus was assessed as Secure, because the species does not meet any of the IUCN Red List criteria for threatened or Near Threatened, or the criteria for Depleted or Declining (the EU27 population or range has not declined by 20% or more since 1980).