SMS Delivery Receipts

A Message Delivery Receipt or Delivery Report (DLR) is a response from the Short Messaging Service Center (SMSC) mobile carriers use to handle SMS messages and provide information about the outbound SMS that was sent out.

Delivery Receipts can help you understand which of your SMSs have been delivered, and which haven’t. In many cases, you also receive information about errors encountered during the SMS delivery process.

Analyzing this data can help you streamline your campaigns by removing numbers that might be inactive or help you decide which actions to take if you are unable to reach a subscriber over SMS.

Delivery Receipt Types

  • Carrier DLR – Indicates the outbound message has reached the carrier SMSC successfully, and it is being processed for delivery to your customer's mobile device. For mobile providers in many countries, confirmation that the message has reached the SMSC is all that is available.

  • Handset DLR – Indicates the outbound message has reached the customer’s mobile device.

Note: For more information about the domestic availability of DLRs, check out Long Codes vs. Toll Free vs. Short Codes. Contact your IntelePeer Solutions Engineer for information on what is available for specific providers in a country.

Items to Consider When Looking at a DLR

  • Not all carriers return DLRs.

  • Some carriers who do return DLRs may not always do so reliably. Carriers across the globe have been known to change this offering without notice; therefore, the lack of a DLR may not indicate an issue with the system.

  • As noted previously, in some cases, a DLR represents the delivery of a message to the SMSC (Carrier DLR), and in others the delivery of a message to the Handset (Handset DLR).

  • Carriers send the DLR back prior to applying SPAM filters. This is done to prevent spammers from trying to circumvent the Carriers SPAM Filter algorithms.

Note: IntelePeer provides an optional parameter on an outbound message to receive DLR status. More information on how to request a Delivery Receipt can be found under our Sending SMS with Delivery Receipts API guide.