The constituency has relatively high economic dependence on agriculture, as well as modern industry (particularly motorsport), research and development, public services and, to a lesser extent, defence. It contains two large market towns, Banbury and Bicester, where the majority of the electorate live. It is a partly rural seat, with the northwest of the constituency on the edge of the Cotswolds. The area has experienced significant urban growth and is popular with commuters who favour its fast transport links to Birmingham, Oxford and London by rail, or the M40. More than one in 10 of the population is employed in higher managerial, administrative and professional work, according to ONS 2011 Census figures for England and Wales. In 2015 the seat was home to 4.3% of EU residents and unemployment was 2.9%. There are some Labour voting wards in Banbury itself, but the remainder of the constituency including Bicester and the smaller rural towns and villages are safely Conservative. However, the 2017 election saw a particularly strong swing for Labour like many towns in southern England. Nonetheless, the Conservative incumbent Victoria Prentis managed to secure a majority of over 12,000, increasing this to nearly 17,000 in 2019.
Under the Redistribution of Seats Act 1885, the Parliamentary Borough was abolished and was reconstituted as the Northern or Banbury Division of Oxfordshire when the three-member Parliamentary County of Oxfordshire was divided into the three single-member seats: Banbury, Woodstock and Henley. It comprised the north-western part of Oxfordshire, including Chipping Norton as well as the abolished borough. Banbury has remained as such since then with varying boundaries (see below).
Banbury has post-World War I unbroken Conservative representation and significant local support for the party. Its MPs since 1922 have all served long terms in office and each since 1922 has been knighted. The seat saw a very close election in 1923. The largest vote since 1922 has at each election been for a Conservative. In 2010 Tony Baldry (Conservative) almost doubled his majority. The 2015 result made the seat the 125th safest of the Conservative Party's 331 seats by percentage of majority.
Four of the six parties' candidates achieved more than the deposit-retaining threshold of 5% of the vote in 2015. In 2001, the Labour Party candidate Lesley Silbey won the largest opposing-party share of the vote since 1974 — 35% of the vote. Prior to 1974, the highest percentage of votes for the second-placed candidate was in 1945 — 48% of the vote.
1885–1918: The Borough of Banbury, and the Sessional Divisions of Banbury and Bloxham, Chadlington, and Wootton North.
1918–1950: The Boroughs of Banbury, Chipping Norton, and Woodstock, the Urban District of Witney, and the Rural Districts of Banbury, Chipping Norton, Witney, and Woodstock.
The constituency was expanded to include the western half of the abolished Woodstock Division, including Witney and Woodstock.
1950–1974: The Boroughs of Banbury, Chipping Norton, and Woodstock, the Urban District of Witney, the Rural Districts of Banbury, Chipping Norton, and Witney, and in the Rural District of Ploughley the parishes of Begbroke, Gosford and Water Eaton, Hampton Gay and Poyle, Kidlington, Shipton on Cherwell, Thrupp, and Yarnton.
Change to contents due to reorganisation of rural districts. Marginal loss to the Oxford constituency as a result of the expansion of County Borough of Oxford.
1974–1983: The Boroughs of Banbury, Chipping Norton, and Woodstock, the Urban District of Bicester, the Rural Districts of Banbury and Chipping Norton, and in the Rural District of Ploughley the parishes of Ardley, Bucknell, Caversfield, Chesterton, Cottisford, Finmere, Fringford, Fritwell, Godington, Hardwick with Tusmore, Hethe, Kirtlington, Launton, Lower Heyford, Middleton Stoney, Mixbury, Newton Purcell with Shelswell, Somerton, Souldern, Stoke Lyne, Stratton Audley, and Upper Heyford.
The Urban and Rural Districts of Witney and the parts of the Rural District of Ploughley, including Kidlington, formed the basis of the new County Constituency of Mid-Oxon. Bicester and northern parts of the Rural District of Ploughley transferred from Henley.
1983–1997: The District of Cherwell wards of Adderbury, Ambrosden, Ardley, Bicester East, Bicester South, Bicester West, Bloxham, Bodicote, Calthorpe, Chesterton, Cropredy, Deddington, Easington, Fringford, Grimsbury, Hardwick, Heyford, Hook Norton, Hornton, Kirtlington, Launton, Neithrop, Otmoor, Ruscote, Sibford, Steeple Aston, and Wroxton, and the District of West Oxfordshire wards of Bartons and Tackley, and Wootton.
Gained a small part of the abolished County Constituency of Mid-Oxon, to the south of Bicester. The bulk of the area comprising the former Urban and Rural Districts of Chipping Norton transferred to the new County Constituency of Witney.
1997–2010: The District of Cherwell wards of Adderbury, Ambrosden, Ardley, Bicester East, Bicester South, Bicester West, Bloxham, Bodicote, Calthorpe, Chesterton, Cropredy, Deddington, Easington, Fringford, Grimsbury, Hardwick, Heyford, Hook Norton, Hornton, Kirtlington, Launton, Neithrop, Otmoor, Ruscote, Sibford, Steeple Aston, and Wroxton.
General Election 1939–40:
Another General Election was required to take place before the end of 1940. The political parties had been making preparations for an election to take place from 1939 and by the end of this year, the following candidates had been selected;
General Election 1914–15:
Another General Election was required to take place before the end of 1915. The political parties had been making preparations for an election to take place and by July 1914, the following candidates had been selected;
Banbury is bordered to the north-east by Northamptonshire South, to the east by Buckingham, to the south by Witney and Henley constituencies, to the east by Stratford-upon-Avon and to the north-east by Kenilworth and Southam.
^ abTancred, Henry William (1969). Trinder, Barrie Stuart (ed.). A Victorian M.P. and his constituents: the correspondence of H. W. Tancred, 1841-1859 (Illustrated ed.). Banbury Historical Society. p. 105.