Though a cell phone is always useful to have close by, there are certain places where your phone should be completely turned off: at a theater performance, on an airplane midflight, at the moment you are getting down on one knee to propose. But never fear–those crucial texts will most likely be received and stored, even if your phone is off.
Attempted Redelivery Period
Most cell service providers will store incoming text messages when your phone has been turned off and periodically attempt to resend the texts until you can receive them. This period of "attempted redelivery" varies depending on your wireless service. AT&T will try to send the text for three days, Verizon for five days, Sprint for a full week.
Default Deletion of Texts
If, at the end of the attempted redelivery period, your cell phone is still turned off (or outside the coverage area of your service provider), only then will the text will be deleted. When you turn your phone on again, there will be no notification that a text has been missed.
Ensuring Text Delivery
Losing a text only becomes an issue when your phone has been turned off for at least three days. Turning your phone on every couple of days, even for just a minute or two, can ensure that you receive all texts sent to you.