For mail servers to communicate and deliver your mail, an eMstamp must be included with the outgoing message from the MTA (Message Transfer Agent). This will cost the outgoing server a number of credits based on a privacy level you or your ISP sets for your mailbox. If the eMstamp doesn't include the required number of credits the mail won't be delivered. If a message is delivered, the receiving server banks the eMstamp credits for reuse.

By being applied at the mail server level eMstamps function transparently for end users of the e-mail system. The only user of the mail system effected by eMstamps will be the spam mailer who is always sending more messages than are received. That is even at a cost of one credit or one tenth of a cent per message, the spammer, sending millions of messages a day, will be seriously impacted by the cost. Most spammers will be put out of business.

Legitimate users of the mail system will be unaffected.