BMB scooped the £2 million account without a pitch, following the demise of the freesheet's previous agency, United London.
Thelondonpaper's head of marketing, Nicole Refson, said: "BMB has been proactive towards thelondonpaper since we launched. We were impressed with its thinking and creativity. United London created a fantastic launch platform and brand identity, so we did not see the need to go through a long pitch process."
The appointment reunites the agency's founding partners, Trevor Beattie and Andrew McGuinness, with NI. During their time at TBWA\London, they worked on The Sun and News of the World accounts for close to a decade.
BMB worked for the Daily Express in 2005, but the newspaper now handles advertising in-house.