* Gordon - A large, blue express engine who is very proud of his speed and strength.
* Henry - A green engine who is often worried and pessimistic, but is also very kind and reliable.
* James - A red engine who is very vain and boastful, but is also very brave and loyal.
* Percy - A small, green engine who is very mischievous and playful, but is also very helpful and hardworking.
* Toby - A brown tram engine who is very friendly and helpful, and is also very good at telling stories.
* Duck - A Great Western Railway engine who is very kind and friendly, and is also very good at shunting.
* Oliver - A Great Western Railway engine who is very strong and reliable, and is also very good at pulling heavy trains.
* Donald and Douglas - Two Scottish twin engines who are very strong and hardworking, and are also very good at working together.
* Daisy - A diesel engine who is very fast and efficient, but is also very arrogant and rude.
* Diesel - A diesel engine who is very strong and powerful, but is also very evil and destructive.
Diesel Engines
* BoCo - A diesel engine who is very friendly and helpful, and is also very good at shunting.
* Derek - A diesel engine who is very strong and powerful, but is also very clumsy and accident-prone.
* Mavis - A diesel engine who is very strong and hardworking, but is also very stubborn and independent.
Electric Engines
* Whiff - An electric engine who is very friendly and helpful, and is also very good at shunting.
* Frankie - An electric engine who is very fast and efficient, but is also very arrogant and rude.
Other Engines
* Thomas - A blue tank engine who is the main character of the series. He is very kind, friendly, and helpful, and is always willing to lend a hand to his friends.
* Edward - A blue engine who is very wise and experienced, and is a good friend and mentor to Thomas.
* Nia - A Kenyan engine who is very strong and hardworking, and is also very kind and friendly.
* Rebecca - A yellow engine who is very fast and efficient, and is also very kind and friendly.
* Caitlin - A red engine who is very fast and efficient, and is also very kind and friendly.
