Three other broadcasters are lining up in partnership with high-street retailers to use the card slot to facilitate loyalty-card schemes and offer high-street discounts to viewers.
The Sky credit card will be positioned as a way to pay for home-shopping through the box and to respond to interactive advertising.
Sky will also use the card to bolster its SkyBet service by enabling accounts to be topped up easily.
The third-party loyalty-card scheme is being pioneered by MiCard, set up by former Carlton Digital director David Sanderson.
One potential application involves a retailer offering £5 discounts on DVDs and CDs to viewers of a music channel. After inserting the loyalty card, viewers will be prompted at regular intervals to confirm via the remote control that they are still watching the channel, for which they will earn points.
Sky confirmed at the end of last year that it would open up the second card slot to enable the operation of broadcast-based loyalty schemes.
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