How to Build Missed Call Text Back (Step by Step)

To build missed call text back, send a text to anyone whose call goes unanswered, usually within a minute, offering a callback or a booking link, and alert staff. You need a number with call events and SMS, a short message, stop rules and, in the US, A2P 10DLC registration.

For small businesses, every missed call can be a lost job. A short text message gets a reply while the caller still cares.

This guide is for agencies and builders setting it up for clients. If you run a business and want it set up for you, that's a done-for-you service at Executive Stride, Josh Pocock's AI agency. It's one of the simplest automations to sell to phone-heavy businesses (trades, clinics, salons, law firms), because the problem is visible: missed calls go to voicemail, and many callers try the next business instead. This guide covers how it works, the build, the messages, compliance and what to measure. It isn't legal advice. It's one of the lead builds on our AI automation examples page.

What you need

• A phone number on a provider with programmable voice and SMS, such as Twilio, or a phone system that sends missed-call events by webhook. If the client keeps their existing number, check how calls forward to the system that can detect a missed call.
• Somewhere to log events: the client's CRM or a small database.
• A booking link the client already uses, or a callback request form.
• A messaging registration (below).

Step 1: Detect the missed call

Missed calls are detected in one of two ways:

1. Forward unanswered calls from the client's main line to a number on your provider after a set number of rings. Your code treats that forwarded call as missed.
2. Use the phone system's own events if it can send a webhook for missed or unanswered calls.

Either way, the result is an event with the caller's number and the time. Save it before doing anything else.

Step 2: Check before you text

Run these checks every time:

• Is it a mobile number? Texts to landlines fail. Many providers offer a lookup to check the line type.
• Has this number opted out? Never text a number that replied STOP.
• Did we already text them recently? Someone who calls three times in five minutes should get one text, not three.
• Is it a known contact who shouldn't get it? Suppliers, staff and existing customers with an open ticket may need a different message or none.

Step 3: Send a short, useful text

Keep it short, say who it's from, and give one clear next step.

Hi, it's Northside Plumbing. Sorry we missed your call. Reply with
what you need and we'll call you back, or book a time here:
[booking link]. Reply STOP to opt out.

After hours:

Hi, it's Northside Plumbing. We're closed right now and missed your
call. Reply with what you need and we'll call you first thing at 8am,
or book here: [booking link]. Reply STOP to opt out.

Set expectations you can meet. If the office won't call back first thing, don't promise it.

Step 4: Handle replies

Replies go to one of three places:

• A booking, written back to the CRM and calendar
• A staff alert with the caller's message, so a person calls back
• An AI reply for simple questions (hours, service area), with anything else handed to a person

Start with staff alerts only. Add AI replies once you've seen a few weeks of real messages and know what people ask. The lead follow-up agent guide covers drafting, approval and stop rules in detail.

The goal of this workflow is to keep the conversation going until the person books or asks for a call. Customize the first text for each client's business.

Compliance: registration and consent

A2P 10DLC registration (US). Twilio's documentation says anyone sending SMS from an application over a regular 10-digit number to the US must register for A2P 10DLC: first a brand (who the sender is), then a campaign (what the messages are and how people opt in and out). Unregistered traffic gets extra carrier fees and more filtering (Twilio's A2P 10DLC overview). Checked October 2026. Budget the registration time into your timeline.

Consent and content. Rules on business texting vary by country and state. A reply to someone who just called, about their call, is different from a marketing message, but get advice for your situation. Keep the text about the missed call, include an opt-out and honour it immediately, and never add the number to marketing lists without separate consent.

Quiet hours. Even for a reply to a call, consider holding texts sent late at night until morning, or use the after-hours message.

What to measure

Record a baseline before launch (missed calls per week from the phone system), then report monthly:

• Missed calls that received a text
• Replies, and how many became bookings or callbacks
• Time from missed call to text
• Opt-outs (a rising number means the message needs work)

How to sell and price it

This is a natural first offer, or an add-on to after-hours voice answering. Price it as a setup fee plus a monthly fee, with SMS usage passed through or included up to a cap. Show the owner their own missed-call count from the phone system on the sales call: it's the most persuasive number you'll have.

Learn to build and run it

The Stride AI Operations course covers running client CRMs, pipelines, voice agents and AI follow-up in StrideOps, the AI operating system Josh Pocock's companies run on, with weekly live calls. Start with the free guide library for setup walkthroughs.

FAQ

How do I send a text after a missed call?

Route unanswered calls to a number on a provider with voice and SMS (or use a phone system that sends missed-call webhooks), then have your automation send a short text with a booking link or callback offer. Check the number is mobile and hasn't opted out before sending.

Do I need to register to send these texts in the US?

If you send from a regular 10-digit long code through an application, A2P 10DLC registration is required, according to Twilio's documentation. You register a brand and a campaign describing the messages and opt-in. Toll-free and short code numbers have separate processes.

Is missed call text back legal?

It can be done compliantly, but rules on business texting vary by country and state. Keep the message about the missed call, include an opt-out and honour it right away, and don't add numbers to marketing lists without consent. Get legal advice for your situation.

Can missed call text back replace answering calls?

No. It catches the calls you miss. Callers with urgent problems may still ring the next business, so answer live whenever you can.

What should the missed call text say?

Say who it's from, apologise for missing the call, and give one next step: reply with what they need, or book a time with a link. Include an opt-out line. Keep it under about 160 characters where you can.