How to Retrieve the Deleted Texts From an iPhone
Just about everyone has deleted a text message or two by accident, but those messages aren't necessarily gone for good if you know what to do. First, try restoring the missing texts with a recent backup copy through iTunes or iCloud; failing that, there's a good chance you can find the texts deep within your phone's internal memory by scanning it with third-party software.
1 Stay Out of Sync
Syncing your iPhone to iTunes or iCloud maintains a backup copy of all your phone's personal files. If you've synced before you deleted your text messages, the missing messages are still in your most recent backup. However, if you sync after deleting those messages, the chances of recovering them drops. Do not sync your iPhone once you discover your messages are missing.
2 Restore Through iTunes
Recovering deleted text messages from a backup via iTunes requires you to connect through your computer. While in iTunes, open the "Summary" tab for your iPhone. Select "Restore Backup" and iTunes will reinstall the most recent backup on your iPhone. This restores any data that was deleted after this backup was made, such as text messages, photos and apps.
3 Restore With iCloud
Your iPhone automatically creates a backup of your data to the iCloud daily when you are within Wi-Fi range, lock your screen and connect to a power source. To restore from an iCloud backup, you'll need to wipe your iPhone first to erase all the current data; tap "Settings | General | Reset | Erase All Content and Settings." Once your data is erased, you're prompted to set your phone up as new or restore from a backup. Select "Restore from iCloud Backup" and enter your Apple ID password.
4 Third-Party Programs
If it's been a while since your last backup, or you've backed up since deleting your text messages, all is not lost. Third-party data recovery software can scan your iPhone for deleted data information and enable you to restore it. This isn't a guaranteed save, as sometimes the data is overwritten, but you have nothing to lose by trying it. Dr. Fone, Tenorshare and EaseUS all offer downloadable software to install on your computer for data recovery purposes. (See Resources.)