It is conducting a pitch to add a direct agency to its roster, which already includes WCRS, Naked Communications and Media Planning Group.
Pitches are well underway and an appointment is expected soon.
Market leader BT is reported to have called in the CID amid claims of a leak of its 118 500 media schedule. The Number took out a series of press ads in national newspapers alongside and parodying BT's own for its new service. BT is also taking legal action, alleging copyright infringement.
The Number, which will fight BT's hold on the 192 directory enquiries services when the market is deregulated, is spending around £20 million on marketing its launch. A direct marketing agency would work on reaching new customers and keeping early customers loyal.
The Number, backed by the US company InfoNXX, has also run TV activity created by WCRS. It features 70s-style runners with moustaches. Sporting vest numbers 118 118, they discuss the merits of directory assistance.
The ads launched the line: "Got your number." Naked worked on the communications strategy.
Press reports have concentrated on confusion among consumers over the price war being waged by the various entrants to the market. The Consumers Association has said people are bewildered by the choice available.