When mail sent from the U.S. is unable to reach its destination, the United States Postal Service, or USPS, will mark it as "undelivered mail returned to sender." There are exceptions to this, such as when the mail is a normal letter, or when a customs department within the country the mail is sent to requests abandonment.
It is sometimes the case that postal forces cannot deliver mail to particular locations. In the case of a normal letter, it is not returned to the sender unless the sender requests this. In addition, some customs departments may ask that the mail is abandoned when it cannot reach its destination.
Circumstances in which postal services cannot deliver mail include:
- The address on the package is insufficient
- The recipient is deceased or no longer lives at the address
- The package remains unclaimed or the recipient refuses it
- The package is prohibited or it has no import license
- The contents are excessive, overweight or cannot reach the recipient for some other reason
If the sender wishes to resend the mail, they must pay for postage again. In some cases, the sender may incur charges for the mail's return. If the recipient has moved to another U.S. address, the sender can resend the mail after paying a forwarding charge.