Abstract: A “lock-and-key” consumer billing data protection capability is provided to telemarketing systems which are based upon previously-acquired consumer lists. The lists contain only partial billing information for each consumer, which is insufficient to access the consumer's account. Thus, at the time a telemarketer employing this capability communicates with a consumer to offer them a product or service, the telemarketer, the seller and any entity hired to perform billing operations for such consumer purchases all remain “locked” out from accessing the consumer's account. When the consumer wishes to authorize the purchase of an offered product or service, the consumer must “reach into their wallet” to provide the “key” to their account, which is the missing billing information not acquired from the third-party list provider.