Bell Pottinger won the work following a competitive pitch.
New West End Company represents more than 600 retailers and property owners across Bond Street, Oxford Street and Regent Street, an area that turns over £8.8bn annually and employs more than 65,000 people.
As well as looking to strengthen stakeholder relations, Bell Pottinger plans to develop a comms programme to support the organisation's business strategy and help prepare its Charter for Growth, a manifesto for change in the West End, to mark the company's 10th anniversary.
Jace Tyrell, deputy chief executive of New West End Company, said: "Our 10th anniversary marks a vitally important period for New West End Company, providing us with the platform to set our agenda for the decade ahead. Bell Pottinger’s corporate and public affairs expertise will enable us to shape and communicate this vision to a broad range of stakeholders, so that the needs of the engine room of the economy are at the forefront of all levels of government and the public’s agenda.
"The mayoral election in 2016 draws closer and we must ensure we have enlightened policies to radically reduce congestion, improve air quality and remove the barriers to economic growth."
Tim Collins, chairman of Bell Pottinger Political, said: "The West End is becoming increasingly central to the UK’s economic performance, with the area producing three per cent of the country’s economic output.
"The chance to work with the organisation representing the area’s businesses is a fantastic opportunity for us as an agency, and the vision and innovation which is central to New West End’s offering will provide new and exciting challenges for our integrated property media and political team to work on over the coming months."
Rain Communications is the retained agency on Bond Street and Oxford Street for lifestyle and major event communications.