Spence's first on-camera role was in second part of the Canadian television miniseries, The Boys of St. Vincent, which was well-received by critics. His next role was in the trilogy of A Family of Cops television movies with Charles Bronson, playing Eddie Fein the younger son of Bronson's character.
Spence's first film role was in the futuristic Anchor Zone, which was filmed in his native Newfoundland. performed in a substantial role in the film Drive, She Said in 1997; the film's storyline and staging were criticized by reviewers. Spence's first leading role was as Cade Foster, in the Space Channel (and later Sci-Fi Channel) original series, First Wave, which ran between 1998 and 2001.
|1997||Drive, She Said||Jonathan Evans|
|1999||Little Boy Blues||That Guy|
|2005||Paper Moon Affair||Vern Staub|
|2006||A Bug and a Bag of Weed||Frehley|
|2007||Crossing||Daniel Cimmerman||also known as Dress to Kill|
|2009||Dr. Dolittle: Million Dollar Mutts||Chad Cassidy||Direct-to-DVD film|
|2011||Crash Site||Daniel Saunders||also known as Crash Site: A Family in Danger|
|2013||12 Rounds 2: Reloaded||Governor Devlin Weaver||Direct-to-DVD film|
|2013||Wolverine: Origin||John Howlett Jr.||Direct-to-DVD film; voice role|
|1993||The Boys of St. Vincent: 15 Years Later||Kevin Reevey age 25||Television miniseries (Part 2)|
|1994–1995||Madison||Cal Sharpe||4 episodes|
|1995||Family of Cops||Eddie Fein||Television movie|
|1995||Robin's Hoods||Episode: "Rock and a Hard Place "|
|1996||The Outer Limits||Young Gerry||Episode: "Paradise"|
|1996||The X Files||Deputy Barney Paster||Episode: "Home"|
|1997||Breach of Faith: Family of Cops II||Eddie Fein||Television movie|
|1997||Dead Man's Gun||Willy||Television movie/backdoor pilot; segment: "My Brother's Keeper"|
|1997||Poltergeist: The Legacy||Noah Wilkes||Episode: "The Devil's Lighthouse"|
|1997–1998||Fast Track||Stevie Servine||Main role, 23 episodes|
|1998–2001||First Wave||Cade Foster||Lead role, 66 episodes|
|1999||Family of Cops III: Under Suspicion||Eddie Fein||Television movie|
|2001||Dark Angel||Charles Smith||Episode: "Hit a Sista Back"|
|2001||Special Unit 2||Ian||Episode: "The Rocks"|
|2001||Strange Frequency||Brad||Episode: "Don't Fear the Reaper"|
|2002||First Shot||Owen Taylor||Television movie|
|2002||Dawson's Creek||Professor Matt Freeman||Recurring role, 5 episodes|
|2002||Glory Days||Greg Embry||Episode: "The Lost Girls"|
|2003||The Lone Ranger||Harmon Hartman||Television movie/backdoor pilot|
|2003||A Crime of Passion||Dale||Television movie|
|2003||Mutant X||Noel||Episode: "Under the Cloak of War"|
|2003||Andromeda||Patrius||Episode: "Conduit to Destiny"|
|2004||The Clinic||Kyle Southern||Television movie|
|2004||Eve's Christmas||Scott||Television movie|
|2004||Stargate SG-1||Delek||Episode: "Death Knell"|
|2004||Bliss||Cable Guy||Episode: "Penelope and Her Suitors"|
|2005||The Collector||The Devil/Dr. Burruss||Episode: "The Pharmacist"|
|2005||Young Blades||Don Marco||Episode: "Four Musketeers and a Baby"|
|2005||Criminal Intent||Devon Major||Television movie|
|2005||Cerberus||Jake Addams||Television movie|
|2005||Third Man Out||Timmy Callahan||Television movie|
|2005||Category 7: The End of the World||FPS Agent Gavin Carr||Television miniseries|
|2005–2006||G-Spot||Paul||Recurring role, 9 episodes|
|2005–2009||Battlestar Galactica||Noel "Narcho" Allison||Recurring role, 9 episodes|
|2006||Shock to the System||Timmy Callahan||Television movie|
|2006||The Obsession||Reed Halton||Television movie|
|2006||To Have and to Hold||Tom Davidson||Television movie|
|2006||Supernatural||Tom||Episodes: "Salvation", "Devil's Trap"|
|2007||Uncaged Heart||Robert Moss||Television movie; also known as Passion's Web|
|2008||Daniel's Daughter||Connor Bailey||Television movie|
|2008||On the Other Hand, Death||Timmy Callahan||Television movie|
|2008||Ice Blues||Timmy Callahan||Television movie|
|2008||NYC: Tornado Terror||Jim Lawrence||Television movie|
|2010||Republic of Doyle||Bobby Maher||Episode: "Blood is Thicker Than Blood"|
|2011||Smallville||Ted Kord||Episode: "Booster"|
|2012||Battlestar Galactica: Blood & Chrome||Lt. Jim "Sunshine" Kirby||Television movie|
|2012||A Mother's Nightmare||Steve||Television movie|
|2013||Stonados||Lee Carton||Television movie|
|2013||Psych||Mayor Gavin Channing||Episode: "Santa Barbarian Candidate"|
|2013–2015||Cedar Cove||Cliff Harting||Recurring role (season 1); main role (seasons 2–3); 29 episodes|
|2014||My Mother's Future Husband||Andrew||Television movie|
|2014||Stolen from the Womb||Rob King||Television movie|
|2015||Accidental Obsession||Ray Johnson||Television movie|
|2015||Driven Underground||Tom Wilcox||Television movie|
|2016||A Wife's Suspicion||Kyle||Television movie|
|2018||Taken Season 2 (TV series)||Senator Warren||Television movie|
|2019-2020||Murdoch Mysteries||Allen Templeton||3 episodes|
- "Sebastian Spence". www.tcm.com. Retrieved 2020-12-29.
- Science Fiction Television Series, 1990–2004: Histories, Casts and Credits for 58 Shows Archived 2020-09-10 at the Wayback Machine. McFarland; 27 September 2013. ISBN 978-0-7864-9183-4. p. 113–.
- "Director, actor Janis Spence dead at 61" Archived 2020-01-09 at the Wayback Machine. CBC News, Feb 07, 2008
- "Actor Sebastian Spence". American Profile. 2002-09-22. Retrieved 2020-12-29.
- Milchael Wilmington (November 11, 1994). "'Boys' Underscores Trauma Of Sexual Abuse". Chicago Tribune. Archived from the original on 2016-03-04. Retrieved 2016-02-23.
- "Painful Look at Pedophilia / `Boys' based on true story of abuse in orphanage" Archived 2018-03-03 at the Wayback Machine. SFGate, Peter Stack, February 3, 1995
- Tom Wiener. The Off-Hollywood Film Guide: The Definitive Guide to Independent and Foreign Films on Video and DVD Archived 2020-09-10 at the Wayback Machine. Random House Publishing Group; 13 August 2002. ISBN 978-0-679-64737-9. p. 92–.
- Adam Sandler (November 21, 1995). "Review: 'A Family of Cops'". Variety. Archived from the original on 2016-03-03. Retrieved 2016-02-23.
- Tony Scott (January 30, 1997). "Review: 'Breach of Faith: Family of Cops II'". Variety. Archived from the original on 2016-03-03. Retrieved 2016-02-23.
- Ray Richmond (January 11, 1999). "Review: 'Family of Cops III'". Variety. Archived from the original on 2016-03-03. Retrieved 2016-02-23.
- "TERROR-NEUVE: Five Horror Films Shot in NL" Archived 2018-03-03 at the Wayback Machine. The Overcast, Lauren Power, October 2, 2015
- "Sophomore effort crashes" Archived 2018-03-03 at the Wayback Machine .Toronto Star - Toronto, Ont. Gerstel, Judy, Sep 4, 1998, Page 1
- Derek Elley. "Drive, She Said" Archived 2018-03-03 at the Wayback Machine. Variety, December 21, 1997
- Ray Richmond (March 18, 1999). "Review: 'First Wave'". Variety. Archived from the original on 2016-03-02. Retrieved 2016-02-22.
- Ed Andreychuk. The Lone Ranger on Radio, Film and Television Archived 2020-09-10 at the Wayback Machine. McFarland; 5 January 2018. ISBN 978-1-4766-2971-1. p. 154–.
- "The Obsession" Archived 2018-03-02 at the Wayback Machine. Radio Times"], review by Sloan Freer (2006)