|Railway Series Portrait|
|Position||Leader of the Ffarquhar Branch Line|
|Age|| 103 (as of 2018)
Built in 1915
|Arrived on Sodor||May 1915|
|Height||12' 8" (3.85 m)|
Thomas is a blue London, Brighton and South Coast Railway Billington E2 0-6-0T tank engine.
Thomas came to the island in May 1915 to be the station pilot at Vicarstown. In Little Western Legacy, eight years later, he was apprenticing Lily on how to run a branch line. He took charge of his own when he helped James after his accident on his first day.
Thomas is a cheeky little engine but has a heart of gold. He's always happy to help out with situations and enjoys running his branch line with Annie and Clarabel.
Thomas is painted in the NWR's standard blue livery with his number in the standard yellow with red border.
Thomas is based on the Billington E2s that were built between 1913 and 1916 for the London, Brighton and South Coast Railway in Southern England (No. 105, according to WNW's model). Thomas' valence is different to the other E2's, as his is straight but the other's are curved. This is due to a rebuild he had in 1960 after a foolish accident by going off to breakfast in a stationmaster's house.
Thomas mentions that he is the last of his kind in Winds of Change.
- Season 1 - Tolerance, The Missing Coach, Great Western (does not speak), Little Western, Night Run, Identity (mentioned) and Snowstorm
- Season 2 - Grand Opening, Old Tricks and Galloping Sausage
- Season 3 - Search Engines, Bluebells and Batsmen (cameo), Storm Report (does not speak), Useful Engines, Comfort Zone, Changes, Bad Water, Suspicions (does not speak), Bygones and Christmas Delivery
- Season 4 - Douglas the Brave (does not speak), Worked Out (cameo), Rough Engines (cameo), Iron Hero, Post and Prejudice
- Barry the Rescue Engine - Back on Track (cameo) and A Troubled Engine (does not speak)
- Season 5 - A Stranger in Need, Little Western Legacy, Doubts (stock footage, cameo), Sheffield's Secret (cameo), Darkest Hour and Desperate Times
- Season 1 STMY - Tornado (cameo), Ode to George Carlin (does not speak), The Missing Engine, Fame and Misfortune (cameo), Doncaster Drawn, Aftermath, Homecoming, Genesis of a Grudge, Consequences (cameo) and Taking Care of Christmas (cameo)
- Season 2 STMY - Swan Song, Percy's Post, Engines of All Trades (cameo), The Thin Clergyman, Dime For Trouble (cameo), Troublesome Trucks (episode) (does not speak) and The Devious Way (cameo)
- Thomas received a brand-new model based on his RWS form in Season 1 STMY by WildNorWester. The new model comes in LB&SC Tuscan and NWR Blue, and also includes variants with and without splashers and a sloped buffer beam from before he crashed into the stationmaster's house. This was later re-scaled for Season 2 STMY when WildNorWester discovered he had built the model to dimensions larger than an E2.