United and Continental currently fly to 370 destinations worldwide, flying 144 million passengers a year. The merger will see the combined group leapfrog American Airlines to become the leading global carrier.
It is expected to fly to 370 destinations in 59 countries - 14 more than Delta Air Lines.
The company will be led by Continental chief executive Jeffrey Smisek. New branding will incorporate the Continental logo and colours but feature the United Airlines brand.
A launch campaign based around the strapline ‘Let's Fly Together' is anticipated, and will point consumers towards a new website.
United Airlines' Glenn Tilton, who will become non-executive chairman of the new company, said: "Building on our Star Alliance partnership, we are creating a stronger, more efficient airline, both operationally and financially, better positioned to succeed in a dynamic and highly competitive global aviation industry."
Continental Airlines' £2 million (US$3 million) UK advertising account has been held by Team Saatchi since November 2008, while the carrier has also worked with creative agency Souk for nearly 20 years. Media planning and buying duties are currently handled by Starcom.
United Airlines' global media arrangements are handled by Mediaedge:cia.