The appointment ends a three-year relationship with Manning Gottlieb OMD, which had repitched for the business alongside sister Omnicom agency Drum.
TSB had asked for media agencies to pitch alongside content shops in a process run by Oystercatchers, with the7stars and Sunday also involved at an earlier stage.
The bank ran the dual agency pitch because, it said, it wants to combine bought media with expertise in creating compelling content across different formats.
TSB’s chief marketing and communications officer Nigel Gilbert said there are a "number of exciting opportunities" to leverage from the bank’s five-year partnership with The Daily Mirror on the Pride of Britain awards.
Vizeum and John Brown will join TSB’s agency roster alongside Joint, which handles advertising, and MRM Meteorite, its direct marketing agency. It is the first time TSB has appointed a specialist content agency.
MG OMD was hired by TSB in November 2013 following its divestment by Lloyds Banking Group. Lloyds was forced to sell TSB after a European Commission ruling that the British government’s purchase of a 43.4% stake in Lloyds Banking Group amounted to state aid.
Following a failed takeover attempt by Co-operative Banking Group, an initial public offering was made for TSB in 2014. Sabadell Bank, the fifth largest bank in Spain, acquired TSB in July 2015.
Gilbert said: "As TSB grows, it is vital that our marketing approach evolves so that we can continue to deliver a differentiated and brand enhancing customer experience in an increasingly digital world.
"We wanted to combine the effective use of bought media with an ability to create compelling content across multiple formats – particularly with a number of exciting opportunities on the horizon following TSB’s partnership with Pride of Britain. This requires a powerful content and media partnership with experienced creators and editorial direction, combined with strong media planning and buying capability. That’s exactly what we’re getting with Vizeum and John Brown."