Work starts on 4 November to provide new safer crossings at Great Cumberland Place at its junction with Marble Arch.
Over 2,500 people cross Great Cumberland Place in front of Marble Arch per hour at peak times, without a fully signalised pedestrian phase.
Works by Transport for London (TfL), with contributions from The Portman Estate and Almacantar, will commence on the evening of 4 November and take place over weekends in November.
A brand new pedestrian phase will be introduced between Pret a Manger and Thomas Cook, and a green phase for cyclists created from Marble Arch itself into Great Cumberland Place.
Work is expected to last four weeks.