Shortly after the demo recording sessions, a record deal with 'Firebox Records' was signed and in late July 2003, over a period of 3 weeks, they completed their first full length album, The Morning Never Came.
In February 2005, Swallow the Sun released their second album, Ghosts of Loss, with their single, "Forgive Her...," gaining 4th place on the Finnish Top 20 singles chart in its first week of release, and stayed there for 6 weeks; the album entering the charts at #8.
In 2006 they signed to 'Spinefarm Records'. In January 2007 they released their third album, Hope, which included a cover version of the Timo Rautiainen & Trio Niskalaukaus song Alavilla Mailla (translation: into "These Low Lands") as a bonus track on the digipack edition and sung by Tomi Joutsen of fellow Finnish metal band, Amorphis with another guest appearance by Jonas Renkse of Katatonia on the song The Justice of Suffering. They then commenced a a US tour with Katatonia, Scar Symmetry and Insomnium in late 2007.
In September 2008, they released the EP, Plague of Butterflies. In October, they announced a December tour of the UK of ten live shows supporting Apocalyptica.
On May 18, 2009 Kai Hahto (ex-Wintersun) will be joining to fill the void left by departing drummer Pasi Pasanen. Later that same year New Moon would be released, followed by Emerald Forest and the Blackbird (2012) followed. In 2014 Hahto would leave to perform with Nightwish's next album and 2015 tour, Juuso Raatikainen replaced him.