DLR (Delivery Reporting)

What is a Delivery Reporting (DLR)?

Delivery Reporting (DLR) is a service provided by mobile carriers that allow users to check the status of a message they have sent. DLR can help users determine whether a message was successfully delivered or not, and provide information about any errors that may have occurred during the delivery process. DLR can also provide useful insights into the performance of a user’s messaging service.

Delivery reporting or DLR is an attribute for every sent message of SMS MT that reports back if the SMS message has been delivered. It is sourced directly from the handset.

Basically, DLRs are URL call-backs for Delivery Reports. Instead of the gateway logging the activity, it will call back the provided URL using a query string (at the end) with the criteria of the delivery statement itself.

What does a DLR report include?

Every DLR includes one of the following four flags that relate to the message status:

• Delivered: The message was successfully delivered to the recipient’s device.
• Scheduled: The message is scheduled for delivery but has not yet been delivered

• Pending: The delivery process is in progress with the mobile operator or may have stalled for some reason, which could include the recipient not having a phone signal, network issues, an issue with their subscription, or their phone is switched off.
• Undeliverable: While pending messages may well get delivered sooner or later, messages that are undeliverable will not. The message could have been blocked by the operator’s spam filters, the number may not exist, or the recipient’s subscription may have been suspended for some reason.

To ensure your messages get delivered to your customers, you have to check if their numbers are active using a number verifier.