Blue Tits breed throughout Europe north to southern Fenno-Scandia and north-central Russia, and in the Caucasus, Turkey, Iran and the eastern side of the Caspian Sea. The African Blue Tit, Cyanistes teneriffae, found in North Africa and the Canary Islands, was previously considered a sub-species of Cyanistes caeruleus but is now recognised as a species in its own right. Blue Tits found in the UK and Ireland are mostly of the sub-species C.c.obscurus, though there have been occasional irruptions from mainland Europe of the nomnate race C.c.caeruleus.
    Blue Tits are found almost everywhere in Great Britain and are particularly common south of a line from the Mersey to the Tees. They are absent only from the highest ground in Scotland, from the Northern Islands, the Outer Hebrides and a few of the islands of the Inner Hebrides.
    In Wiltshire Blue Tits are common in all areas except in some parts of Salisbury Plain and a few other open downlands lacking trees for nesting and feeding. They are particularly numerous in the north and southwest of the county. Birds of Wiltshire recorded them in 885 terads, with confirmed or probable breeding in 760 of them; WTA2 recorded them in 899 tetrads with breeding in 706.
The following references are used throughout these species accounts, in the abbreviated form given in quotation marks:
1968-72 Breeding Atlas” – Sharrack, J.T.R. 1976:  The Atlas of Breeding Birds in Britain and Ireland. T. & A. Poyser
1981-84 Winter Atlas” – Lack, P.C. 1986:  The Atlas of Wintering Birds in Britain and Ireland. T. & A. Poyser
1988-91 Breeding Atlas” – Gibbons, D.W., Reid, J.B. & Chapman, R.A. 1993: The New Atlas of Breeding Birds in Britain and Ireland 1988-91. T. & A. Poyser
Birds of Wiltshire” – Ferguson-Lees, I.J. et al. 2007 : Birds of Wiltshire, published by the tetrad atlas group of the Wiltshire Ornithological Society after mapping fieldwork 1995-2000. Wiltshire Ornithological Society.
“Bird Atlas 2007-2011” – Balmer, D.E., Gillings, S., Caffrey, B.J., Swann, R.L., Downie, I.S. and Fuller, R.J. 2013: Bird Atlas 2007-2011: the Breeding and Wintering Birds of Britain and Ireland
WTA2” – ("Wiltshire Tetrad Atlas 2 ") the present electronic publication, bringing together the Wiltshire data from “Birds of Wiltshire” and “Bird Atlas 2007-11”, together with data from further fieldwork carried out in 2011 and 2012.
"Hobby" - the annual bird report of the Wiltshire Ornithological Society.