It replaces incumbent contractor JB Riney in July on a deal estimated to be worth £10m a year, with an option to extend for a further five years
The scope will see FM Conway deliver construction and maintenance services across carriageways, footways, bridges, street lighting and drainage systems.
The new partnership will see FM Conway build upon its success of delivering high-profile projects on London’s historic infrastructure, such as the recent refurbishment of London Bridge.
James Tallon, managing director at FM Conway, said: “This is a pivotal moment in FM Conway’s future and an incredibly exciting partnership for us.
“With our continued drive for smart solutions, our ability to adapt through new technologies and our drive for low carbon alternatives, we will work with the City of London Corporation to deliver an accessible, sustainable and well maintained public realm that respects the City’s unique heritage.”