You will need
  • Full access to the phone on which you want to restore SMS, including all passwords and documentation, computer, Internet access, pre-download software to recover data, the card reader is for SIM cards.
Accept the fact that in most cases recovery deleted SMS impossible. But on some phones it is possible to restore deleted messages, because they are not deleted immediately at the command of the user, and stored some time in the memory device. Therefore, carefully review the menu items on your phone or read the instruction. If your phone has a "Trash or Deleted items folder messages , you're in luck and you will likely be able to recover lost messages.
Some devices, such as smartphones from Nokia, automatically transmit all the messages on the phone in a special folder on your computer. If your mobile device does not support this capability, then connect it to PC via DATA cable and try to restore SMS using special recovery programs.
Download software for data recovery on hard drives and removable media. One of the most popular is Undelete. Such programs can recover data even on formatted media.
Do not contact the mobile operators with the request to recover deleted SMS, they are such a service not provided. Just wasting time which can be precious in a critical situation.
To recover deleted SMS also can be using a card reader for SIM cards. In Russia such devices are imported from the USA. They represent a removable storage device, similar in appearance to a conventional flash. In the hole on the case the reader is placed in the SIM card and then it will scan and restore the deleted messages.