| Hugh Bonneville | Robert Crawley, Earl of Grantham |
| Laura Carmichael | Lady Edith Crawley |
| Jim Carter | Charles Carson |
| Raquel Cassidy | Baxter |
| Brendan Coyle | John Bates |
| Michelle Dockery | Lady Mary Crawley |
| Kevin Doyle | Joseph Molesley |
| Joanne Froggatt | Anna Bates |
| Lily James | Lady Rose MacClare |
| Robert James-Collier | Thomas Barrow |
| Allen Leech | Tom Branson |
| Phyllis Logan | Mrs. Hughes |
| Elizabeth McGovern | Cora Crawley, Countess of Grantham |
| Sophie McShera | Daisy Mason |
| Lesley Nicol | Mrs. Patmore |
| Maggie Smith | Violet Crawley, Dowager Countess of Grantham |
| Penelope Wilton | Isobel Crawley |
| Matthew Goode | Henry Talbot |
| Alun Armstrong | Stowell |
| James Faulkner | Lord Sinderby |
| Penny Downie | Lady Sinderby |
| Matt Barber | Atticus Aldridge |
| Sue Johnston | Miss Denker |
| Jeremy Swift | Spratt |
| Douglas Reith | Lord Merton |
| Rade Serbedzija | Prince Kuragin
(as Rade Sherbedgia) |
| Hannah Wood | Brancaster Kitchen Maid |
| Jane Lapotaire | Princess Irina |
| Jonathan Coy | George Murray |
| Sebastian Dunn | Charlie Rogers |
| Harry Hadden-Paton | Bertie Pelham |
| Alice Patten | Diana Clark |
| Michael Fox | Andy |
| Oliver Barker | George Crawley
(uncredited) |
| Zac Barker | George Crawley
(uncredited) |
| Fifi Hart | Sybbie Branson
(uncredited) |
| Stephen Mason | Prison Guard
(uncredited) |
| Anthony Milton | Veteran in Crowd
(uncredited) |
| Jason Nicholls | Rules Patron
(uncredited) |
| Eva Samms | Marigold Gregson
(uncredited) |
| Karina Samms | Marigold Gregson
(uncredited) |
| Graham Saxon | Dinner guest
(uncredited) |