Tory-held marginal seats
| # | Constituency | Region | Tory majority | 2nd placed party | Swing needed to unseat | Current Tory MP |
|---|---|---|---|---|---|---|
| 1. | Southampton Itchen | South East | 31 | Labour | 0.03% | Royston Smith |
| 2. | Richmond Park | London | 45 | Lib Dems | 0.04% | Zac Goldsmith |
| 3. | Stirling | Scotland | 148 | SNP | 0.15% | Stephen Kerr |
| 4. | St Ives | South West | 312 | Lib Dems | 0.3% | Derek Thomas |
| 5. | Pudsey | Yorkshire & Humber | 331 | Labour | 0.31% | Stuart Andrew |
| 6. | Hastings & Rye | South East | 346 | Labour | 0.32% | Amber Rudd |
| 7. | Chipping Barnet | London | 353 | Labour | 0.32% | Theresa Villiers |
| 8. | Thurrock | East of England | 345 | Labour | 0.34% | Jackie Doyle-Price |
| 9. | Preseli Pembrokeshire | Wales | 314 | Labour | 0.37% | Stephen Crabb |
| 10. | Calder Valley | Yorkshire & Humber | 609 | Labour | 0.52% | Craig Whittaker |
| 11. | Norwich North | East of England | 507 | Labour | 0.55% | Chloe Smith |
| 12. | Broxtowe | East Midlands | 863 | Labour | 0.78% | Anna Soubry |
| 13. | Stoke-on-Trent South | West Midlands | 663 | Labour | 0.8% | Jack Brereton |
| 14. | Telford | West Midlands | 720 | Labour | 0.81% | Lucy Allan |
| 15. | Bolton West | North West | 936 | Labour | 0.92% | Chris Green |
| 16. | Aberconwy | Wales | 635 | Labour | 0.99% | Guto Bebb |
| 17. | Northampton North | East Midlands | 807 | Labour | 1% | Michael Ellis |
| 18. | Hendon | London | 1,072 | Labour | 1.03% | Matthew Offord |
| 19. | Mansfield | East Midlands | 1,057 | Labour | 1.05% | Ben Bradley |
| 20. | Middlesbrough S & E Cleveland | North East | 1,020 | Labour | 1.07% | Simon Clarke |
| 21. | Milton Keynes South | South East | 1,725 | Labour | 1.34% | Iain Stewart |
| 22. | Northampton South | East Midlands | 1,159 | Labour | 1.41% | Andrew Lewer |
| 23. | Pendle | North West | 1,279 | Labour | 1.43% | Andrew Stephenson |
| 24. | Milton Keynes North | South East | 1,915 | Labour | 1.5% | Mark Lancaster |
| 25. | Morecambe & Lunesdale | North West | 1,399 | Labour | 1.53% | David Morris |
| 26. | Finchley & Golders Green | London | 1,657 | Labour | 1.58% | Mike Freer |
| 27. | Camborne & Redruth | South West | 1,577 | Labour | 1.63% | George Eustice |
| 28. | Putney | London | 1,554 | Labour | 1.66% | Justine Greening |
| 29. | Harrow East | London | 1,757 | Labour | 1.73% | Bob Blackman |
| 30. | Watford | East of England | 2,092 | Labour | 1.78% | Richard Harrington |
| 31. | Copeland | North West | 1,695 | Labour | 1.97% | Trudy Harrison |
| 32. | Morley & Outwood | Yorkshire & Humber | 2,104 | Labour | 2.01% | Andrea Jenkyns |
| 33. | Vale of Glamorgan | Wales | 2,190 | Labour | 2.04% | Alun Cairns |
| 34. | Corby | East Midlands | 2,690 | Labour | 2.24% | Tom Pursglove |
| 35. | Cheltenham | South West | 2,569 | Lib Dems | 2.25% | Alex Chalk |
| 36. | Swindon South | South West | 2,464 | Labour | 2.4% | Robert Buckland |
| 37. | Worcester | West Midlands | 2,490 | Labour | 2.42% | Robin Walker |
| 38. | Gordon | Scotland | 2,607 | SNP | 2.43% | Colin Clark |
| 39. | Crawley | South East | 2,457 | Labour | 2.44% | Henry Smith |
| 40. | Blackpool N & Cleveleys | North West | 2,023 | Labour | 2.47% | Paul Maynard |
| 41. | Chingford & Woodford Green | London | 2,438 | Labour | 2.6% | Iain Duncan Smith |
| 42. | Reading West | South East | 2,876 | Labour | 2.78% | Alok Sharma |
| 43. | Derbyshire North East | East Midlands | 2,861 | Labour | 2.84% | Lee Rowley |
| 44. | Ayr, Carrick & Cumnock | Scotland | 2,774 | SNP | 3% | Bill Grant |
| 45. | Carlisle | North West | 2,599 | Labour | 3.02% | John Stevenson |
| 46. | Southport | North West | 2,914 | Labour | 3.04% | Damien Moore |
| 47. | Ochil & S Perthshire | Scotland | 3,359 | SNP | 3.1% | Luke Graham |
| 48. | Rossendale & Darwen | North West | 3,216 | Labour | 3.21% | Jake Berry |
| 49. | Angus | Scotland | 2,645 | SNP | 3.29% | Kirstene Hair |
| 50. | Truro & Falmouth | South West | 3,792 | Labour | 3.35% | Sarah Newton |
| 51. | Scarborough & Whitby | Yorkshire & Humber | 3,435 | Labour | 3.4% | Robert Goodwill |
| 52. | Walsall North | West Midlands | 2,601 | Labour | 3.41% | Eddie Hughes |
| 53. | Stevenage | East of England | 3,384 | Labour | 3.43% | Stephen McPartland |
| 54. | Carmarthen W & Pembrokeshire S | Wales | 3,110 | Labour | 3.68% | Simon Hart |
| 55. | Devon North | South West | 4,332 | Lib Dems | 3.89% | Peter Heaton-Jones |
| 56. | Loughborough | East Midlands | 4,269 | Labour | 3.94% | Nicky Morgan |
| 57. | Cities of London & Westminster | London | 3,148 | Labour | 4.07% | Mark Field |
| 58. | Filton & Bradley Stoke | South West | 4,182 | Labour | 4.12% | Jack Lopresti |
| 59. | Cheadle | North West | 4,507 | Lib Dems | 4.13% | Mary Robinson |
| 60. | Clwyd West | Wales | 3,437 | Labour | 4.23% | David Jones |
| 61. | Moray | Scotland | 4,159 | SNP | 4.37% | Douglas Ross |
| 62. | Shipley | Yorkshire & Humber | 4,681 | Labour | 4.38% | Philip Davies |
| 63. | Renfrewshire East | Scotland | 4,712 | SNP | 4.38% | Paul Masterton |
| 64. | Banff & Buchan | Scotland | 3,693 | SNP | 4.43% | David Duguid |
| 65. | Erewash | East Midlands | 4,534 | Labour | 4.55% | Maggie Throup |
| 66. | Worthing East & Shoreham | South East | 5,106 | Labour | 4.81% | Tim Loughton |
| 67. | Sherwood | East Midlands | 5,198 | Labour | 4.87% | Mark Spencer |
| 68. | Lewes | South East | 5,508 | Lib Dems | 5.08% | Maria Caulfield |
| 69. | Gloucester | South West | 5,520 | Labour | 5.1% | Richard Graham |
| 70. | Nuneaton | West Midlands | 4,739 | Labour | 5.14% | Marcus Jones |
| 71. | Colchester | East of England | 5,677 | Labour | 5.3% | Will Quince |
| 72. | Aberdeen South | Scotland | 4,752 | SNP | 5.34% | Ross Thomson |
| 73. | St Albans | East of England | 6,109 | Lib Dems | 5.36% | Anne Main |
| 74. | Uxbridge & South Ruislip | London | 5,034 | Labour | 5.39% | Boris Johnson |
| 75. | Wimbledon | London | 5,622 | Labour | 5.46% | Stephen Hammond |
| 76. | Dumfries & Galloway | Scotland | 5,643 | SNP | 5.47% | Alister Jack |
| 77. | Plymouth Moor View | South West | 5,019 | Labour | 5.53% | Johnny Mercer |
| 78. | Shrewsbury & Atcham | West Midlands | 6,627 | Labour | 5.69% | Daniel Kawczynski |
| 79. | Rochford & Southend East | East of England | 5,548 | Labour | 5.87% | James Duddridge |
| 80. | Halesowen & Rowley Regis | West Midlands | 5,253 | Labour | 5.92% | James Morris |
| 81. | Altrincham & Sale West | North West | 6,426 | Labour | 6.09% | Graham Brady |
| 82. | Wycombe | South East | 6,578 | Labour | 6.15% | Steve Baker |
| 83. | Dover | South East | 6,437 | Labour | 6.19% | Charlie Elphicke |
| 84. | Wells | South West | 7,582 | Lib Dems | 6.23% | James Heappey |
| 85. | Hazel Grove | North West | 5,514 | Lib Dems | 6.25% | William Wragg |
| 86. | South Thanet | South East | 6,387 | Labour | 6.42% | Craig Mackinlay |
| 87. | East Devon | South West | 8,036 | Independent | 6.65% | Hugo Swire |
| 88. | South Ribble | North West | 7,421 | Labour | 6.77% | Seema Kennedy |
| 89. | Rushcliffe | East Midlands | 8,010 | Labour | 6.87% | Kenneth Clarke |
| 90. | Cornwall North | South West | 7,200 | Lib Dems | 7.07% | Scott Mann |
| 91. | Welwyn Hatfield | East of England | 7,369 | Labour | 7.13% | Grant Shapps |
| 92. | York Outer | Yorkshire & Humber | 8,289 | Labour | 7.22% | Julian Sturdy |
| 93. | Stafford | West Midlands | 7,729 | Labour | 7.44% | Jeremy Lefroy |
| 94. | Swindon North | South West | 8,335 | Labour | 7.59% | Justin Tomlinson |
| 95. | Kingswood | South West | 7,500 | Labour | 7.69% | Chris Skidmore |
| 96. | Aberdeenshire West & Kincardine | Scotland | 7,949 | SNP | 7.7% | Andrew Bowie |
| 97. | Harlow | East of England | 7,031 | Labour | 7.84% | Robert Halfon |
| 98. | Macclesfield | North West | 8,608 | Labour | 7.93% | David Rutley |
| 99. | Rugby | West Midlands | 8,212 | Labour | 8% | Mark Pawsey |
| 100. | Stourbridge | West Midlands | 7,654 | Labour | 8.12% | Margot James |