Season 21 is an Upcoming season in 2017 animated by Jam Filled Entertainment.
- Hasty Hannah - a new coach comes to the railway to temporarily replace Henrietta.
- Dowager Hatt's Busy Day - Dowager Hatt takes Sir Topham Hatt's place for the day, but confusion, delay, and trouble kicks in.
- Emily in the Middle - Emily gets trapped in the middle on the bridge of Ulfsted Mine.
- Rosie's New Livery - Rosie gets a new paint job so that the Troublesome Trucks don't recognize her.
- The Piggy Pond - Farmer Trotter asks Percy and Charlie to watch over the pigs in their mud pond.
- Thomas Won't Lose - Thomas tries not to get beaten by Diesel 10, who uses illegal fuel to win.
- Ashima Returns - Ashima comes to work on the railway and saves Thomas from the Troublesome Trucks.
- Stuck in the Hills - When Daisy thinks Harvey is crazy on crates, she gets stuck on a hillside by a big crate.
- Emily and Edward
- Super Rescue
- Mountain Engine
- Bad Look-Out
- Danger Points
- Devil's Back
- Let's Set Friendship Into Motion
- Come for the Ride (different footage and choir)
- Arry and Bert
- Peter Sam
- Annie and Clarabel
- Troublesome Trucks
- Slip Coaches
- Jerome and Judy
- Sir Topham Hatt
- Dowager Hatt
- Mr. Percival
- Jem Coll
- Farmer McColl
- Farmer Trotter
Duck, Oliver, Toad, Donald, Douglas and Flying Scotsman are also likely to appear.
Characters Introduced Edit
- This season will contain the 500th episode of the show.