The company said her role would be to support the new ‘I am Train’ campaign and be responsible for the development and execution of consumer and corporate PR activity.
O’Neill will report to commercial director Simon Darling, who said: "Lorna’s expertise and passion for developing integrated campaigns will be key to building Trainline brand awareness across earned and owned media."
The news follows Trainline’s acquisition by US private equity firm KKR in January, which derailed plans to float the business on the stock market with a reported value of around £500m.
O’Neill, who also has PR agency experience at Brazen and has worked on brands such as Hasbro and Gumtree Australia, said: "Having recently rebranded and with extensive product development in the pipeline, it is such a fantastic time to join Trainline. There’s a real opportunity for us to develop multi-channel, creative campaigns that will reach our customers and help them to travel smarter by rail."
Grosvenor House's PR team is now led by Nick Barrington-Wells, who joined from agency Dragon Associates.