Constituency profile

Swindon South

South West · Borough constituency · Swindon borough

Heidi Alexander MP
Sitting MP

Heidi Alexander

Labour

First elected July 2024Cabinet: Secretary of State for Transport

Current PollCheck projection

Region & type
South West
Borough constituency, Swindon council
Last 5 GE winners
CCCCL
Conservative 4/5, Labour 1/5
EU referendum 2016
54.5% Leave
UK average 51.9%; +2.6pp above mean
Current outlook
Labour +6.7pp
vs Reform UK 29.4%
SouthernBrexit-marginal

About the Swindon South constituency

Swindon South is a borough constituency in the South West, covering most or all of Swindon. The sitting MP is Heidi Alexander (Labour), first elected in July 2024.

At the 2024 general election, Labour won Swindon South with 48.4% of the vote, ahead of the Conservatives on 26.9%, a majority of 9,606 votes. Turnout was 61.7%.

If a general election were held today, PollCheck's projection at the current seven-poll average has Labour on 36.1% and Reform UK on 29.4% in Swindon South, a margin of 6.7 points. The projection updates automatically as new polls are added.

Demographically, Swindon South is closely divided in the 2016 EU referendum (an estimated 54.5% voted Leave in 2016). About 28.4% of residents hold a degree, 59.1% of homes are owner-occupied, and the seat has a median age of about 39 (2021 Census).

Across the last 5 general elections on record, the seat has been won by the Conservatives 4 times, Labour 1 time (earlier years may be on predecessor boundaries).

Who lives in Swindon South? Constituency demographics

From the 2021 Census and 2016 EU referendum estimates. Constituency-level data on 2024 boundaries.

Leave vote 2016
54.5%
UK average ~52%
Degree or above
28.4%
UK average ~34%
No qualifications
17.8%
UK average ~18%
Owner-occupied
59.1%
UK average ~63%
Renting (social + private)
39.5%
UK average ~36%
Median age
38.9
UK median ~40
Age 65+
18.1%
UK average ~19%
Age 18-34
31.5%
UK average ~28%

How did Swindon South vote in 2024 and how would it vote now?

2024 vote shares from the HoC Library. Current projection is at the 7-poll average.

2024 general election

Lab gain from Con · majority 9,606 votes (21.5pp) · turnout 61.7%

Current projection

If a general election were held today, at current poll average

Map of Swindon South

Switch between ward-level 2024 election winners and a demographic view. Ward winners are Britain Elects' / New Statesman modelled estimates with an average ~4pp margin of error per ward. The demographic view splits the seat into small neighbourhoods (around 1,500 residents each, from the 2021 Census). Hover any area for detail.

Council layer (not Westminster)

Swindon South within Swindon

The Westminster constituency of Swindon South sits entirely within Swindon Council. Local council elections are a separate ballot from Westminster general elections - the figures below are from the council elections held on Thursday 7 May 2026.

Council overlap

CouncilShare of seatProjection
Swindon
68 LSOAs
100%View projection ›

Most recent council ward results

Latest council winner per ward. Where the council held a May 2026 election, those results are shown; otherwise we show the most recent available ward result (via DCLEAPIL, 2014-2024), or, where the seat was uncontested at the last election, the current sitting councillor from OpenCouncilData. The "Shift since GE2024" column is only computed for May 2026 results - earlier council votes pre-date the GE, so no directional shift is shown.

Ward GE2024 winner Latest council winner Shift since GE2024 Turnout

Projection trajectory

PollCheck's projection for Swindon South at each of the last 60 GB polls. Hover the chart for the underlying poll details.

Who has won Swindon South at past general elections?

2024 result is on current boundaries. The 2019 row is the UK Parliament's notional recalculation onto the 2024 boundaries (directly comparable to 2024). The 2010, 2015 and 2017 rows are on the boundaries in force at the time and aren't directly comparable.

Year Result MP Lab Con LD Right (Ref/UKIP) Green Other Majority Turnout
2010predecessorCon gain from LabRobert Buckland South Swindon MP34.3%41.8%17.6%4.3% UKIP1.3%0.7%3,54464.9%
2015predecessorCon holdRobert Buckland South Swindon MP34.5%46.2%3.7%12.0% UKIP3.6%-5,78566.6%+1.7
2017predecessorCon holdRobert Buckland South Swindon MP43.6%48.4%4.1%2.5% UKIP1.5%-2,46470.8%+4.2
2019notionalConservative winnerRobert Buckland South Swindon MP, pre-review boundary40.2%51.6%7.6%-0.5%0.1%5,65068.3%
2024Lab gain from ConHeidi Alexander48.4%26.9%4.1%13.8% Ref5.7%1.1%9,60661.7%-6.6

Swindon South was created or substantially redrawn by the 2023 boundary review. Pre-2024 rows below are for the predecessor seat South Swindon (the seat that covered most of this area), so vote shares and majorities aren’t directly comparable to the post-2024 figures.

Constituencies most like Swindon South

Five seats with similar demographic profiles to Swindon South. Politics shown for context.

What would change this seat?

Move the sliders to set national vote shares. The per-seat projection updates live. Reset returns to the current 7-poll average.

Related

Sources

If you spot a data issue, please let us know.