Northern is upgrading its Class 333 trains with improvements including high-definition CCTV cameras, USB charging points and plug sockets.
The trains, which run between Skipton and Bradford Forster Square, and Leeds and Ilkley, will also get brighter LED lighting and digital display screens that provide customers will real time information.
The improvements are part of a wider, multi-million-pound investment programme to enhance customer journeys with new trains and better stations.
Tricia Williams, chief operating officer at Northern, said: “Our customers are at the heart of everything we do, and we are committed to delivering further improvements for our passengers to enjoy.
“I am grateful to our partners across the industry, including Angel Trains, Yellow Rail and our own team at Northern, who have worked hard to deliver the refurbishments and I look forward to seeing more and more refurbished carriages take to the rails in the coming months.”
David Jordan, chief operating officer of Angel Trains, said: “It is exciting to see the Class 333s undergo refurbishment which will dramatically improve journeys for Northern passengers.
Northern is the second largest train operator in the UK, with nearly 2,000 services a day to more than 500 stations across the North of England.