|Percy the Small Engine|
|Occupation: Mail engine|
|First Appearance: Troublesome Engines|
| Performer: Nigel Pilkington (UK)|
Christopher Ragland (US)
Percy is a small, energetic, saddle tank engine.
Percy is the No. 6 green engine and is the junior member of Sir Topham Hatt's railway. He is Thomas' best friend and his favorite job is delivering the mail.