1. Identify the business immediately
Unknown-number texts create suspicion. Put the business name in the first sentence and connect the message to the call they just made.
2. Explain the missed call in one human sentence
"We're with a customer" or "Our team could not answer" is enough. Avoid a long apology or pretending the response was manually typed. Helpful automation does not need to hide what it is.
3. Promise only what the team can deliver
"Within two working hours" is better than "ASAP" if it reflects reality. Use separate business-hours and after-hours versions so a message sent at 10 pm does not create an impossible expectation. See what should happen in the first five minutes after an enquiry for how this fits the wider response sequence.
4. Ask for context, not an application form
A plumber may ask for a postcode and a short description. A clinic may ask for a preferred appointment time but should avoid inviting sensitive medical detail into an unsecured text. Ask only for what changes the next action.
5. Make replies go somewhere visible
If the customer can reply, someone must be able to see and own the conversation. Test the full return path—not just whether the first outbound message was sent.
Want a sense of what a faster reply is worth in practice? Try the lead response revenue calculator with your own call volume.