The constituency is in the former Northumberland Coalfield where mining and shipbuilding were once significant industries. Residents' incomes and wealth are slightly below average for the UK.[4]
In the 2019 general election, Blyth Valley was the third seat to declare and the first Conservative victory of the election,[5] pointing towards many similar Conservative victories in Labour's Red Wall[6] as the night went on.
Bedlington was transferred to the re-established constituency of Wansbeck. Small area in the south (Backworth and Earsdon), which was now part of the metropolitan borough of North Tyneside in Tyne and Wear, transferred to Wallsend.
2007 boundary review
In the fifth periodic boundary review of parliamentary representation in Northumberland, which came into effect for the 2010 general election, the Boundary Commission for England recommended that no changes be made to the Blyth Valley constituency.[13]
In 2009, a further government reorganisation resulted in the abolition of all local government boroughs and districts in Northumberland and the establishment of the county as a unitary authority. Accordingly, although this has not affected the current constituency boundaries, the constituency now contains the Northumberland County Council wards of: Cowpen, Cramlington East, Cramlington Eastfield, Cramlington North, Cramlington South East, Cramlington Village, Cramlington West, Croft, Hartley, Holywell, Isabella, Kitty Brewster, Newsham, Plessey, Seghill with Seaton Delaval, South Blyth, and Wensleydale.
^Craig, F.W.S., ed. (1972). Boundaries of parliamentary constituencies 1985-1972. Chichester, Sussex: Political Reference Publications. pp. 82, 140. ISBN 0-900178-09-4.
^Fifth Periodical Report. Cm 7032-iv(PDF). Vol. 4 (Mapping for the Non-Metropolitan Counties and the Unitary Authorities). London: Her Majesty's Stationery Office. 2007. ISBN 978-0101-703222.