Hybrid mail is mail that is delivered using a combination of electronic and physical delivery.^[1] Usually, it involves digital data being transformed into physical letter items at distributed print centres located as close as possible to the final delivery addresses. An e-mail letter (also L-mail and letter mail) is a letter which is sent as an email using a computer, then printed out and delivered as a traditional (physical) letter.

It is a communication means between the cyber and the material world. The system was invented by UK company CFH, who launched their Hybrid Mail solution Docmail in 2008^[2]. The printer or mail transfer agent prints the electronic mail on paper, the mail transport agent packs it into an envelope and the mail delivery agent or postman delivers it to the receiver's mailbox. Generally there is a fee for this service; however very small amounts and single email letters may be free of charge depending on the service provider and generally fees are much lower than cost incurred in sending the mail directly or by using a franking machine. Research shows that in the UK, for a simple enclosed letter, posted 2nd class, the saving could be as much as much as 40% per letter.^[3]

There are also reverse systems, where handwritten letters can be delivered as email. This mail scanning service, sometimes called letter email, is increasingly popular with businesses and individuals who wish to access their mail from another country. However, special care must be taken to inspect local laws and the service provider's scanning practices to ensure that they are not reading the mail or acting on behalf of the client from a legal standpoint.^{[citation needed]}