Nuttall was born in Bolton, Greater Manchester. She was educated at Bury Grammar School for Girls and trained at Tring Park School for the Performing Arts. She performed with the National Youth Music Theatre, notably playing the lead role of Princess Ismene in Aurelius at the Tyne Opera House, Newcastle and the Assembly Rooms in Edinburgh in August 1997.

In the Autumn of 2005, Nuttall toured the UK extensively as Eliza Doolittle in My Fair Lady to critical acclaim. She shared the role with Lisa O'Hare on the National Tour due to other commitments with her first album. The tour started on 5 October 2005 at the Palace Theatre in Manchester and ended on 12 August 2006 at the Wales Millennium Centre in Cardiff. In October 2006 she made her West End début as Sister Sarah Brown in Guys and Dolls at the Piccadilly Theatre appearing opposite both Don Johnson and Patrick Swayze.

In January 2007, Nuttall performed on BBC Radio 2's Friday Night is Music Night with an 80-piece live orchestra and in May 2007, she joined the cast of the stage revival of Boeing-Boeing at the Comedy Theatre opposite Patricia Hodge, Mark Rylance and Roger Allam. On 2 October 2007, Nuttall replaced Kim Medcalf in the London production of Cabaret at the Lyric Theatre, transferring directly from her role in Boeing-Boeing. In April 2008, Nuttall's initial six-month contract was extended until the production's closure on 21 June. Nuttall appeared in Hotel Babylon in 2009 as Melanie Hughes, the new hotel receptionist.

In June and July 2010, Nuttall played one of the lead roles in the revival of the hit musical The Hired Man at the Octagon Theatre, Bolton. Later that year she returned to the Octagon Theatre, Bolton to play Stella Kowalski in the Tennessee Williams classic A Streetcar Named Desire. She shared the role of the Lady of the Lake in the UK tour of Spamalot, which began on 18 October 2010 at the Edinburgh Playhouse. From September 2011, Nuttall began appearing in series two of Downton Abbey, appearing as the new maid, Ethel.

In December 2011 she appeared in Noises Off at London's Old Vic until March 2012. On 14 July 2011, Nuttall was awarded the Honorary Degree of Doctor of Arts by the University of Bolton. On 8 June 2013 Nuttall starred in the Saturday Drama on BBC Radio 4. Entitled The Weather Girl she played the lead role of Abigail, a prisoner whose mental state is assessed by a clinical Psychologist.

Nuttall dated fellow Emmerdale star Ben Freeman for four years. She married long-term boyfriend, the actor Andrew Buchan, on 8 September 2012. Their first child was born in 2015.