More than 600 more West London stores and restaurants have signed up to accept the card, which has been distributed to 86,000 households, in the latest leg of the scheme run by Big Issue founder John Bird and his daughter Diana.
The card gives access to a wide range of discounts and deals at independent traders to encourage shoppers to make more use of the independent retailers in their communities, rather than shopping at "cloned" chains, Diana Bird said.
The card will be free for the first year, but will cost £10 to renew from August 2011. It was first rolled out in Camden, where more than 100 retailers currently accept the cards used by 5,000 cardholders.
The scheme, which is open only to businesses with nine or fewer branches, has been endorsed by Conservative Party leader David Cameron, who owns a Wedge card and claims to use it regularly in his local stores.