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Missed-call text-back

You're elbow-deep in a water heater and miss a call. The caller doesn't leave a voicemail. They call the next plumber.

⏱ Setup: 1-2 hours📶 Beginner🧩 n8n workflow

See the full setup Get the ready-to-import template

How it works

Get a Twilio phone number and set it to forward calls to your cell.
If you don't answer within ~20 seconds, Twilio tells the n8n workflow the call was missed.
The workflow texts the caller within seconds: 'Sorry we missed you, what's going on?'
When they reply, AI writes a short, friendly answer and you get an email alert with their number and message.
You call back when you're free, already knowing what the job is.

Tools used

Twilio n8n OpenAI API Gmail / Google Workspace

Realistic monthly cost≈ $8.73 + €20/mo

How we got this number

Twilio local number$1.15
Texting registration (A2P 10DLC) monthly fee$2
~200 text segments sent + received$1.66
carrier fees on ~100 outbound texts$0.50
~150 inbound call minutes$1.28
~150 minutes forwarded to your cell$2.10
~100 AI-written replies$0.04
Automation platform (or self-host n8n free)€20

Assumes ~100 missed calls a month. n8n Cloud Starter is billed in euros; self-hosting n8n removes that line. Prices are list prices checked 2026-10-26; see every source.

Plus one-time texting registration (A2P 10DLC): about $19.50 (low-volume brand + campaign vetting). Source

The full setup, step by step

12 steps in one n8n workflow. Everything below is generated from the template itself, so it always matches.

Before you start

You need an n8n account (n8n, or self-host it free) plus your own logins for: Twilio Gmail / Google Workspace OpenAI API.

How the automation flows

When a call ends

1Call ended (from Twilio)3Config (edit me)4Call or text?call 5Tell Twilio what to say 6Was the call missed?if yes7Text the caller 8Email the owner

When someone texts you

2Incoming text 3Config (edit me)4Call or text?text 9Acknowledge Twilio (text)10AI writes reply 11Text the AI reply 12Email owner about the text

Tap a step to jump to its details.

Each step and what it does

1
Trigger
Call ended (from Twilio)
Twilio calls this webhook the moment a call to your business number ends, rings out or goes to voicemail. It passes along the caller's number and the call status.
Webhook pathYOUR_N8N_URL/webhook/missed-call
Then → 3. Config (edit me)
2
Trigger
Incoming text
Twilio calls this webhook every time someone texts your business number.
Webhook pathYOUR_N8N_URL/webhook/incoming-sms
Then → 3. Config (edit me)
3
Settings
Config (edit me)
One place for everything specific to your business. Every later step reads from here, so this is the only node you have to edit.
Editthe settings table below
Then → 4. Call or text?
4
Decision
Call or text?
Both triggers share the same Config, so this splits them: calls go one way, texts the other.
Rulethe call status is filled in
Calls → 5. Tell Twilio what to say · Texts → 9. Acknowledge Twilio (text)
5
Reply to request
Tell Twilio what to say
Answers Twilio right away. If the call was answered it just hangs up; if it was missed the caller hears a short message saying a text is on its way.
Sendsthe message shown under Message copy
Then → 6. Was the call missed?
6
Decision
Was the call missed?
Only keeps going when nobody picked up. Answered calls stop here, so nobody gets a pointless text.
Rulethe call status is not “completed”
If yes → 7. Text the caller · If no → stops here
7
Send SMS (Twilio)
Text the caller
Sends the missed caller a text within seconds.
Sendsthe message shown under Message copy
🔑 Connect your Twilio login on this node
Then → 8. Email the owner
8
Send email (Gmail)
Email the owner
Emails you so you know who to call back (and what they were told).
Sendsthe message shown under Message copy
🔑 Connect your Gmail login on this node
End of this path.
9
Reply to request
Acknowledge Twilio (text)
Tells Twilio the text was received. The reply goes out separately, so this one sends nothing to the customer.
Then → 10. AI writes reply
10
AI (OpenAI)
AI writes reply
OpenAI drafts a short, on-brand reply using your business info and the customer's message. The instructions (prompt) keep it short and stop it from inventing prices.
Modelgpt-5-mini
AI instructions (prompt)
You are the friendly dispatcher for a local plumbing and HVAC company. Write one short, warm SMS reply (under 300 characters) to a new lead. Acknowledge their problem in plain words, say a technician will call them shortly, and if they describe water actively leaking, gas smell, no heat in freezing weather or no AC in extreme heat, tell them to reply URGENT. Never quote prices. Never promise an exact arrival time. Sign off with the business name.
🔑 Connect your OpenAI login on this node
Then → 11. Text the AI reply
11
Send SMS (Twilio)
Text the AI reply
Texts the AI's reply back to the customer.
Sendsthe message shown under Message copy
🔑 Connect your Twilio login on this node
Then → 12. Email owner about the text
12
Send email (Gmail)
Email owner about the text
Emails you what the customer wrote and what was sent back.
Sendsthe message shown under Message copy
🔑 Connect your Gmail login on this node
End of this path.

Key settings to change

All of these live in the Config (edit me) node. Change them once and every text and email updates.

Setting	Placeholder in the template	Change it to
Business name `business_name`	`YOUR BUSINESS NAME`	Exactly how customers know you. It appears in every text.
Booking / calendar link `booking_link`	`https://YOUR-BOOKING-LINK`	Your online booking page (Calendly, your CRM's scheduler, or your contact page). Use the short public link.
Hours `hours`	`Mon-Fri 8am-6pm`	Short and text-friendly, e.g. Mon-Fri 8am-6pm.
Your email `owner_email`	`you@example.com`	Where the 'new lead' and 'missed call' alerts go.
Your cell `owner_cell`	`+15555550100`	In +1 format (+15551234567).
Twilio number `twilio_number`	`+15555550199`	The number you bought in Twilio, in +1 format. Texts are sent from it.

Message copy: exactly what it sends

Highlighted parts are filled in automatically. Edit the wording right in the node.

Voice to the caller (spoken) · step 5

Sorry we missed you. We are texting you right now.

SMS to [their phone number] · step 7

Hi, this is business name. Sorry we missed your call! We're probably on a job. Reply with what's going on (leak, no heat, no AC, etc.) and your address, and we'll call you right back. If it's an emergency, reply URGENT.

Email to [your email] · step 8

Subject Missed call from their phone number

We missed a call from their phone number and texted them automatically. Call them back when you can.

SMS to [their phone number] · step 11 AI-written each time

AI-written reply

Email to [your email] · step 12

Subject New text from their phone number

They wrote: their text

We auto-replied: AI-written reply

Hook it up

Open Config (edit me) and fill in your business name, booking link, hours, email, cell and Twilio number.
Click each node with a red warning and connect your own Twilio, OpenAI, Gmail credentials.
In Twilio, on your number: Voice > 'A call comes in' > TwiML Bin with:
<Response><Dial timeout="20" action="YOUR_N8N_URL/webhook/missed-call">+1YOURCELL</Dial></Response>
Messaging > 'A message comes in' > Webhook YOUR_N8N_URL/webhook/incoming-sms (POST).
Register your number for A2P 10DLC in Twilio before texting customers.
Activate the workflow.

Test it before you trust it

Fill in every setting in Config (edit me) and connect your logins on the nodes with a red warning.
In Twilio, paste the Production webhook URLs (…/webhook/…, not …/webhook-test/…) on your number, then activate the workflow.
From a different phone, call your Twilio number and let it ring out. You should hear the short message and get the text within about 10 seconds.
Check your inbox for the “Missed call from …” email.
Call again and answer it. No text should go out.
From another phone, text a real question (“Can you come out today?”). You should get a short AI reply and an email with both messages.
Open Executions in n8n. Every run should be green. A red node tells you exactly which step to fix.
Texts not arriving? The usual cause is A2P 10DLC registration still pending in Twilio.

Skip the clicking

Get the ready-to-import n8n template

Every step above, already wired up. Paste it into n8n, add your logins, fill in your business info and you're live.

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