People working for contractors employed by Westminster City Council will get paid the London Living Wage as a minimum.
The council is the latest to insist that contractors who want to do business with it pay their employees the wage, which currently stands at £10.75 an hour.
It means that contractors will also get the wage, which the council had already signed up to for its own staff.
The move follows other councils, including City of London, which insist that contractors also pay the London Living Wage.
It means that 22 local authorities in London, including Hammersmith and Fulham, Tower Hamlets and Redbridge, are fully signed up to the voluntary scheme.
A third are not listed by the Living Wage Foundation. Westminster city council’s chief executive Stuart Love said: “As a City for All, we’re enormously proud of being accredited as a London Living Wage employer.
“We are nothing without our staff and those who represent us. In Westminster we have some of the very best and it’s only right that they should be paid properly.
“We believe that should apply right across the board whether the staff work directly for us or come from a contractor.”