Transport for London has shortlisted Adam & Eve/DDB, M&C Saatchi, Ogilvy and incumbent VCCP for its creative account.
TfL kicked off the statutory review in August and expects to announce a winner in spring 2020. The process is being run through the Official Journal of the European Union with the help of AAR.
The longlist also included Abbott Mead Vickers BBDO and FCB Inferno.
The brief includes work for other Greater London Authority departments, including the London Fire Brigade, the Metropolitan Police and the London Legacy Development Corporation.
The winning shop will pick up a three-year contract with the option to extend it for another year.
Miranda Leedham, head of customer marketing and behaviour change at Transport for London, said: "We are undertaking a statutory review of our creative account for marketing and behaviour change projects, which includes through-the-line marketing, such as cinema and radio advertising, social media, content creation, print design and below-the-line.
"As the role of marketing continues to evolve, and as we become more commercially focused, we are taking this opportunity to ensure that we have the best arrangements in place to meet future challenges and ensure best value. We’re delighted with the level of interest that we received and are looking forward to working with the shortlisted bidders and seeing their proposals."