What’s a handset block?


Daisy Phimmasone


If the end user (recipient) no longer wants to receive messages from the sending number, they can implement a handset block. In such cases, the handset will reject your messages and you’ll receive an API error code 4753 (SMPP error code 753).

What kind of traffic does error code 4753 apply to?

API error code 4753 (SMPP error code 753), or destination-rejected-handset, applies to the traffic that has made it to the carrier and was rejected downstream by the handset. The standard toll-free Verizon outbound surcharge applies.

Can carriers other than Verizon return a 4753 error?

Yes, the only carrier that doesn’t return a 4753 error is AT&T. However, they still include a handset block as a reason under API error code 4750. 

How can I remediate a handset block?

A handset block can occur due to a variety of reasons. Since it’s usually the end user of the handset that implements the block, they would have to be the ones to remove it in order to start receiving your messages again. Some other common reasons are:

  • A prepaid user whose account is out of money
  • A subscriber that’s provisioned to not receive this type of SMS/MMS
  • An SMS that was sent to an Internet of Things (IoT) device

Please have the destination subscriber (handset end user) contact their carrier if they wish to receive your messages. If none of the above reasons apply, please open a ticket with your Bandwidth Support Team or hit us up at (855) 864-7776!

Article is closed for comments.