Text Santa, ITV's festive appeal to help six charities, culminates tonight with a special appeal show but throughout the day there have been fundraising events.
And stars of West End shows got in the spirit of things this afternoon, by singing Christmas carols in Leicester Square.
Here's our Arts and Entertainment Correspondent Lucrezia Millarini.
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People took to the streets of Brixton today to march against what they see as the 'gentrification' of the area.