Mayor Boris Johnson says 174,000 men and women are missing out on an extra 35-pounds a week.
So as part of his "Know Your Rights" campaign, he's urging the capital's older residents - and their carers - to check they're getting all the payments they're entitled to.
The details now from Liz Wickham.
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An English springer spaniel given to the UK Border Force has become a star new recruit for sniffing out smuggled cash.
Celine Dookhran, 20, was allegedly kidnapped by her relative Mujahid Arshid, 33, and his employee Vincent Tappu, 28, on July 19 last year.
Collins hid the device, two sim cards and two memory sticks inside a crutch while on remand in September.