Glossary
What is Delivery receipt?
A delivery receipt (DLR) is a status report from the mobile network saying whether a text reached the recipient's phone.
A network can't confirm a text has arrived until the handset acknowledges it. If the phone is off or out of signal, the network holds the text and keeps trying for a while, so a receipt can come back within seconds or not until hours later. A failure usually means the number isn't in service or the network gave up.
A courier firm in Croydon texting 'Your parcel arrives between 1pm and 3pm' can see which customers' phones received it and ring the ones that didn't before the van sets off.
In CaptiFi Connect each text has a status timeline (queued, sent, then delivered or undelivered, or failed if it never left us), and you can filter message history by status and export it as CSV. The message.delivered and message.failed webhooks tell your own system as soon as a receipt arrives. Texts that fail before they leave are refunded; a text that leaves and then goes undelivered isn't.