The company, which operates more than one in five local bus services and a number of freight train lines, is seeking an agency to handle a large web-build project that will produce a central website for the company's transport businesses.
These include: First Great Western, First ScotRail, First Capital Connect, First Trans- Pennine Express, Hull Trains and First GBRf.
The hunt for a digital shop follows the travel operator concluding a review of its £10 million media planning and buying account. FirstGroup appointed MEC Manchester to the business in August.
It is understood that the company's roster of creative agencies, including Covey McCormick, Dig For Fire, Guerilla Marketing and LiveFX, will not be affected by the process.
A spokesman for FirstGroup confirmed that the transport company was seeking a digital agency.