Registered mail

Registered mail is a paid system that records a letter and keeps it secure through the mails and on to the receiver. Typically, a number is assigned to a letter or package for that purpose and someone must sign for it.

Special markings, typically with "R", are used to mark such mail. This can include a handstamp or label that will include the number.

 File:US 1954 regd cover.jpg|A 1954 US registered airmail cover with return receipt requested. Note the "R" handstamp with the registration number. The back view (bottom) has mailing office postmarks struck to detect any tampering. The receiving office postmark is struck on the back as well. 

Special stamps have been issued for the service.  File:NSW reg.jpg|New South Wales. File:US registration.jpg|United States. 

Registration labels
Registration labels have been used in order to have unique numbers for mail. They have been also collected, though full registered covers are very much preferred.

In some cases, they have used provisionally as stamps. They were surcharged when New Guinea was occupied by British forces. Iran has used unnumbered ones as postage when its lowest values had run out, in both plain and overprinted form. Dates of use of the below examples are unknown.  File:Cartagena reg label.jpg|Cartagena, Colombia. File:Asuncion reg label.jpg|Asuncion, Paraguay. File:Portugal reg label.jpg|Lisboa (Lisbon), Portugal. File:Thailand reg label.jpg|Phrae, Thailand. 

[[Category:R]]