August 6th 2015 (5)
August 13th 2015 (6)
August 18th - 20th 2015 (4)
August 27th 2015 (1)
Collated by MiddleEnglander
There were 16 by-elections in August with 5 (31%) changing hands. The results can be summarised by:
| Party | Candidates | Defended | Retained | Gained | Lost | Won | Retention Rate |
| Conservative | 14 | 3 | 2 | 2 | 1 | 4 | 67% |
| Labour | 14 | 4 | 3 | 1 | 3 | 75% | |
| Liberal Democrat | 11 | 1 | 1 | ||||
| SNP | 7 | 6 | 6 | 1 | 7 | 100% | |
| Plaid Cymru | 1 | ||||||
| UKIP | 13 | 1 | 1 | 0% | |||
| Green | 13 | 1 | 1 | 0% | |||
| Independent | 4 | ||||||
| Christian | 1 | ||||||
| Libertarian | 1 | ||||||
| Mebyon Kernow | 1 | ||||||
| No Description | 1 | 1 | 1 | 0% | |||
| North East | 1 | ||||||
| Pirate | 1 | ||||||
| Orkney Manifesto | 1 | 1 | 1 | ||||
| Scottish Socialist | 1 | ||||||
| TUSC / TUSAC | 2 | ||||||
| Yorkshire First | 1 | ||||||
| Total | 88 | 16 | 11 | 5 | 5 | 16 | 69% |
Conservatives gained 2 seats and lost 1
- gained Cornwall, Pendarves from UKIP on a ~12% swing since 2013 with UKIP coming fourth behind a Liberal Democrat and Labour
- gained Exeter, Pinhoe from Labour with ~1% swing since 2014, ~6¾% since 2012 and a marginal swing fom Labour since 2010
- lost Powys, Glasbury to a Liberal Democrat who had not contested the seat in recent years
- the recently elected MP had gained the seat in 2012 from an Independent who had been returned unopposed in 2008 and 2004
SNP gained Glasgow, Langside from Green who had won the seat in 2012 with just 9.1% of first preference votes
Orkney Manifesto gained Orkney, West Mainside from No Description who had founded and was now sitting as Orkney Manifesto
Elsewhere Conservatives retained Warwickshire, Whitestone with an increased majority of 35% over Labour
and West Oxfordshire, Witney North with a much reduced majority of 8% over a Liberal Democrat,
Labour retained 3 former "coalfield" seats polling over 50% in all cases whilst
SNP retained 6 seats with swings over Labour since 2012 of approaching 20% or more.
