We don’t charge for messages sent to mobile numbers that are clearly invalid (e.g., invalid country code or incorrect number format). Our system attempts to detect these issues before a message is sent to the network.
When you attempt to send a message, we run two checks:
Number format check – Is the number in a valid format?
Prefix check – Does the number have a valid prefix that is registered with a mobile network?
If a number fails either of these checks, the message will not be sent to the network, and you won’t be charged. These invalid recipients are excluded and won’t appear in your reports.
If a number passes both checks, we cannot confirm if the number is truly valid until we submit it to the network for delivery. At this point, the message is considered sent, and you will be charged, even if the carrier later returns a failed delivery status.
As with all other gateways, we charge for every message that is sent to the network. If a message fails delivery, we automatically retry free of charge for up to 72 hours.
Once a message reaches a final status of Failed, no further attempts will be made.
What causes a message to fail?
There are a heap of reasons why an SMS doesn't reach its destination. All of these are out of our control. When an SMS is sent using our platform, we forward it onto the mobile networks nearly instantly.
Some of the most common reasons for a message to fail are:
Phone is out of signal
Phone is switched off
There is an account issue with the users phone plan
The users inbox is full (normally on older phones)