| Year | Title | Role | Notes |
| 1983 | Mansfield Park | Maria Bertram | 5 episodes |
| 1985 | Agatha Christie's Miss Marple | Julia Simmons | Episode: "A Murder is Announced" |
| Theatre Night | Rose Trelawny | Episode: "Trelawny of the 'Wells |
| 1986 | The Understanding | Kate | TV film |
| 1987 | Rumpole of the Bailey | Elizabeth "Miz Liz" Probert | 4 episodes |
| 1989 | The Ginger Tree | Mary Mackenzie | All 4 episodes |
| Screen One | Sue | Episode: "One Way Out" |
| 1990 | Agatha Christie's Poirot | Stella Robinson | Episode: "The Adventure of the Cheap Flat" |
| 1991 | The Black Candle | Bridget Mordaunt | TV film |
| 1992 | Inspector Morse | Helen Marriat | Episode: "Dead on Time" |
| Thacker | Ginny Morgan | TV film |
| 1994 | Screen Two | Sally | Episode: "Return to Blood River" |
| 1995 | Tears Before Bedtime | Sarah Baylis | 4 episodes |
| Ghosts | Maddy | Episode: "The Chemistry Lesson" |
| Under the Moon | Francesca Jenson | TV film |
| 1996 | In Suspicious Circumstances | Daisy Holt | Episode: "The Great Romancer" |
| 1997 | Family Money | Isabel | Episode: |
| Mr. White Goes To Westminster | Helen Nash MP | TV film |
| The Ruby Ring | Mary Spencer | TV film |
| Thief Takers | Carol Mason | Episode: "Sisters in Arms" |
| 1998–2000 | The Bill | Mary McMahon | 3 episodes |
| 2000 | The Bookfair Murders | Marsha Hillier | TV film |
| Harry Enfield's Brand Spanking New Show | Various | 12 episodes |
| 2001 | The Hunt | Lady Patricia Whitton | TV film |
| NCS: Manhunt | DS Maureen Picasso | 8 episodes |
| The Bombmaker | Patsy | TV film |
| Kavanagh QC | Sarah Swithen | Episode: "The End of Law" |
| Midsomer Murders | Suzanna Chambers | Episode: "Destroying Angel" |
| 2003 | Canterbury Tales | Jane Barlow | Episode: "The Wife of Bath" |
| 2004 | DNA | Kate Donovan | All episodes |
| 2005 | The Murder Room | Caroline Dupayne | Both 2 episodes |
| 2005–2006 | Donovan | Kate Donovan | 3 episodes |
| 2007 | Fanny Hill | Mrs Cole | 2 episodes |
| Mobile | Rachel West | Episode: "The Boss" |
| The Inspector Lynley Mysteries | Vivienne Oborne | Episode: "Limbo" |
| 2007–2008 | The Sarah Jane Adventures | Mrs Wormwood | 3 episodes |
| 2007–2014 | Outnumbered | Auntie Angela | 10 episodes |
| 2008 | Midsomer Murders | Arabella Hammond | Episode: "Shot at Dawn" |
| Distant Shores | Lisa Shore | All 12 episodes |
| Hotel Babylon | Caroline | Episode: |
| 2009 | Lark Rise to Candleford | Celestia Brice Coulson | Episode: |
| Agatha Christie's Marple | Sylvia Savage | Episode: "Why Didn't They Ask Evans?" |
| Heartbeat | Sylvia Swinton | Episode: "Deadlier Than the Male" |
| The Queen | Queen Elizabeth II | Episode: "Us and Them" |
| 2010 | New Tricks | Anne Gorton | Episode: "Left Field" |
| 2010–2015 | Downton Abbey | Lady Rosamund Painswick | 18 episodes Nominated - Screen Actors Guild Award for Outstanding Performance by an Ensemble in a Drama Series |
| 2011 | Midsomer Murders | Kate Cameron | Episode: "Death in the Slow Lane" |
| 2013 | Playhouse Presents | Woman | Episode: "The Call Out" |
| 2015–2016 | Home Fires | Frances Barden | All 12 episodes Nominated - Satellite Award for Best Actress – Miniseries or Television Film |
