| Hugh Bonneville | Robert Crawley, Earl of Grantham |
| Laura Carmichael | Lady Edith Crawley |
| Jim Carter | Charles Carson |
| Brendan Coyle | John Bates |
| Michelle Dockery | Lady Mary Crawley |
| Kevin Doyle | Joseph Molesley |
| Siobhan Finneran | Sarah O'Brien |
| Joanne Froggatt | Anna Bates |
| Robert James-Collier | Thomas Barrow
(as Rob James-Collier) |
| Allen Leech | Tom Branson |
| Phyllis Logan | Mrs. Hughes |
| Elizabeth McGovern | Cora Crawley, Countess of Grantham |
| Sophie McShera | Daisy Mason |
| Matt Milne | Alfred Nugent |
| Lesley Nicol | Mrs. Patmore |
| Maggie Smith | Violet Crawley, Dowager Countess of Grantham |
| Ed Speleers | Jimmy Kent |
| Dan Stevens | Matthew Crawley |
| Penelope Wilton | Isobel Crawley |
| Kenneth Bryans | Nield |
| MyAnna Buring | Edna Braithwaite
(as Myanna Buring) |
| Ron Donachie | Mr. McCree |
| Charles Edwards | Michael Gregson |
| Peter Egan | Hugh 'Shrimpie' MacClare, Marquess of Flintshire |
| Shaun Hennessy | Tug-of-War Judge |
| John Henshaw | Jos Tufton
(as Jon Henshaw) |
| Lily James | Lady Rose MacClare |
| Simone Lahbib | Wilkins |
| Phoebe Nicholls | Susan MacClare, Marchioness of Flintshire |
| David Robb | Dr. Clarkson |
| Cara Theobold | Ivy Stuart |
| William Travis | Stall Keeper |
| Stuart Ward | Thug |
| Laura Hydari | Maid |
| Jonathan Brooks | Fairgoer
(uncredited) |
| Jessica Brown Findlay | Lady Sybil Branson
(uncredited) |
| David G. Robinson | Prosecutor
(uncredited) |