Bridget Hatt was born in 1943 to Charles Topham Hatt and Amanda Croarie, two years after her brother. In 1951, the Hatts spent a long holiday on Toby's old line in East Anglia. Stephen was excited when he first met Toby, but Bridget accidentally offended him by assuming he was an electric tram.
Bridget, like her brother, has never been shown to age, and has always stayed the same age ever since the first season. She and her brother helped Toby to find an abandoned castle. When it was her birthday, James was sent to collect her and take her to the town hall, and she took a liking to the pink undercoat he was painted in. She later caught chickenpox along with Stephen, convincing Henry that engines could also catch chickenpox.
Once, she, along with her brother and grandfather were supposed to take a tour around Arlesburgh Harbour on Skiff, however the rail boat thought he saw a mermaid and went to sea with just her grandfather aboard, to her and Stephen's distress. Eventually, Harold and Captain found them. Bridget was also part of a group of VIPs that Hugo took on a rail tour from Knapford to Vicarstown and back.
In the Railway Series and the first two seasons of the television series, Bridget wore a white dress with red markings. Since the third season, she has worn a pink dress over a white blouse.
- 1987 - The Island of Sodor: Its People, History and Railways (mentioned)
- Season 1 - Toby and the Stout Gentleman
- Season 2 - Thomas Comes to Breakfast (cameo)
- Season 3 - Percy's Promise (cameo), Time for Trouble (cameo), Gordon and the Famous Visitor (cameo), Thomas Gets Bumped (cameo), Diesel Does it Again (cameo), Edward, Trevor and the Really Useful Party (cameo), Buzz, Buzz (cameo), All at Sea (cameo) and Bulgy (cameo)
- Season 5 - Lady Hatt's Birthday Party (deleted scene cameo), Toby and the Flood (cameo), Toby's Discovery, Thomas and the Rumours (not named), Happy Ever After (cameo) and Sir Topham Hatt's Holiday
- Season 6 - Harvey to the Rescue (cameo), No Sleep for Cranky (stock footage cameo), Scaredy Engines (cameo), Percy and the Haunted Mine (cameo), James and the Red Balloon (cameo) and Thomas, Percy and the Squeak (stock footage cameo)
- Season 7 - Emily's New Coaches (cameo), Edward's Brass Band (cameo), The Refreshment Lady's Tea Shop (cameo), Bad Day at Castle Loch (cameo), Rheneas and the Roller Coaster (cameo), Snow Engine (cameo), Bulgy Rides Again (cameo), Harold and the Flying Horse (cameo), Best Dressed Engine (cameo) and Three Cheers for Thomas (cameo)
- Season 8 - Thomas and the Tuba (cameo), Henry and the Wishing Tree (cameo), Thomas Saves the Day (cameo), Emily's New Route (cameo), Thomas and the Firework Display (cameo), Squeak, Rattle and Roll (cameo), Thomas and the Circus (cameo) and James Goes Too Far (cameo)
- Season 9 - Percy and the Oil Painting (cameo), Mighty Mac (cameo), Thomas' Milkshake Muddle (cameo) and Thomas Tries His Best (cameo)
- Season 10 - Follow that Flour (cameo), A Smooth Ride (cameo), Thomas and the Jet Plane (cameo), Percy and the Funfair (cameo), Seeing the Sights (cameo), Which Way Now?, Sticky Toffee Thomas (cameo), Thomas and the Treasure (cameo) and James the Second Best (cameo)
- Season 11 - Thomas and the Storyteller (cameo), Smoke and Mirrors (cameo), Toby's Triumph (cameo), Thomas and the Runaway Car (cameo), Edward and the Mail (cameo), Wash Behind Your Buffers (cameo), Percy and the Left Luggage (cameo), Ding-a-Ling (cameo) and Duncan Does it All (cameo)
- Season 13 - Tickled Pink and Thomas and the Runaway Kite
- Season 14 - Diesel's Special Delivery and Pop Goes Thomas (cameo)
- Season 15 - Wonky Whistle (cameo)
- Season 16 - Muddy Matters (cameo)
- Season 17 - Wayward Winston (not named; does not speak)
- Season 19 - Henry Spots Trouble, Diesel's Ghostly Christmas (cameo) and Reds vs. Blues (cameo)
- Season 20 - Engine of the Future and Skiff and the Mermaid
- Season 21 - Confused Coaches
- Calling All Engines! (cameo)
- The Great Discovery (cameo)
- Day of the Diesels
- Sodor's Legend of the Lost Treasure (cameo)
- The Great Race (cameo)
- 1993 - Thomas and the Toboggan!
- 1994 - Well Caught!
- 1996 - A Day at the Beach!, Play Time!, The Thomas Kart!, The Brown Bear and Lost Property!
- 1997 - 'Smile, Please!', The Daisy Chain and Bobbing About!
- 1998 - The Snow Engine!, Look Alike, The Carnival!, The Easter Cake!, Toby and the Stout Gentleman! (does not speak) and The Train Game
- 2001 - The Pop Show, Rolling Around! and Skating Show!
- 2002 - Toby to the Rescue!
- 2003 - Playbus, Seaside Search! (cameo), Cook Controller! (not named; mentioned), Really Fast Food!, Percy's Party! (cameo) and Feeding Time (cameo)
- 2004 - Snow Engine (cameo), Percy the Pirate (does not speak), Night Lights and Holiday Hat (does not speak)
- 2005 - Model Engines and Working Christmas
- 2006 - Passenger Plane, Busy Bee and The Snow Controller
- 2007 - Canal Cruise and Snow Surprise
- 2008 - Giant Puffer and A Spring Clean! (does not speak)
- 2010 - Rope Rescue, Launching Lizzie, Piggy-in-the-middle!, Tickled Pink (not named), Proud Puffers and Thomas and the Kites (does not speak)
- 2011 - Tickled Pink (not named) and Thomas and the Kites (does not speak)
- 2012 - Prize Guys
- 2013 - The Railway Rink and New Year Party
- 2014 - Kite Flying and Thomas and the Kites (does not speak)
- 2016 - Tickled Pink! (not named; does not speak) and Henry Spots Trouble (does not speak)
- 2017 - Thomas and the Kites (does not speak)
Bridget Hatt also appeared in the magazine stories, A Colourful Christmas, A Friend's Party, A Hole in One, Daisy and the Fish, Doctors and Nurses, Dressing Up, Fair Scare!, Feeding Time, Gone Fishing, Harvest Time, Keeping Dry, Lights On, Misbehaving, Puzzles, Retirement Time, Snap Happy, Station Mystery, The Christmas Sacks, The Flower Dome, The Hallowe'en Special, The Tiny Engine and Working Whistles.
- 1996 - Pantomime Pranks
- Teresa Gallagher (UK; thirteenth season onwards - US; nineteenth season onwards)
- Jules de Jongh (US; thirteenth and fourteenth season only)
- Chisato Nakajima (Japan; first season only)
- Tomoko Naka (Japan; Toby's Discovery only)
- Hiromi Nishida (Japan; fifth season only)
- Yuko Mizobe (Japan; tenth and thirteenth seasons)
- Hiro Nakajima (Japan; fourteenth season only)
- Sakura Yoshioka (Japan; Day of the Diesels onwards)
- Justyna Bojczuk (Poland; thirteenth season onwards)
- Lena Meieran (Norway; thirteenth - fourteenth seasons)
- Blanche Ravalec (France and French speaking Canada; tenth season onwards)
- Leyla Rangel (Latin America; thirteenth season onwards)
- Susa Saukko (Finland; thirteenth season onwards)
- Leonie von Ungern-Sternberg (Germany; Audio Books only)
- Elain Llwyd (Wales)
- Vina Papadopoulou (Greece)
- In the magazine story, The Hallowe'en Special, it is said that Stephen and Bridget live on the Mainland and come to stay with Lady and Sir Topham Hatt once in a while.
- In the television series, Bridget's hair colour is brown. In Toby the Tram Engine and the magazine stories, it is blonde.
- In Thomas Comes to Breakfast, Bridget appeared as the Stationmaster's daughter.
- A large scale head of Bridget Hatt is preserved by The Coffey Man Preservation from The Prop Gallery.
- In the magazine stories, she and Stephen have a friend named Marcus.