How do I set up two-way SMS for customer support?

To set up two-way SMS for customer support, you need a phone number customers can text, a system to receive and reply to those texts, and a process for routing messages to your team.

1) Choose an SMS provider

Pick a platform that supports inbound and outbound messaging, such as:

• Twilio
• MessageBird
• Vonage
• Plivo
• Sinch
• Or a helpdesk with SMS built in, like Zendesk, Freshdesk, Intercom, etc.

Look for:

• Two-way SMS support
• Webhooks/API for incoming messages
• Shared inbox or agent routing
• MMS support if you need images
• Compliance tools and opt-in management

2) Get a business phone number

You’ll need a number that supports texting:

• Local number: good for regional support
• Toll-free number: good for national support
• Short code: high volume, more setup, usually more expensive
• Alphanumeric sender ID: often not two-way in many countries

For the US/Canada, be aware of A2P 10DLC registration requirements for business texting.

3) Connect inbound messages to your support system

Set up a way for incoming texts to land in your support workflow. Common options:

Option A: Shared inbox

Customers text one number, and your team replies from a team inbox.

• Simplest setup
• Good for small to mid-sized teams

Option B: Helpdesk integration

Route SMS into Zendesk/Freshdesk/Intercom as tickets or conversations.

• Better for larger support teams
• Easier SLA tracking and reporting

Option C: Custom app/API

Use webhooks to send incoming SMS to your backend, then display them in a custom dashboard.

• Most flexible
• Requires development

4) Configure webhooks for incoming texts

Your provider will send incoming SMS events to your server via a webhook. Your app should:

• Receive the inbound message
• Identify the customer by phone number
• Create or update a support ticket/conversation
• Notify an agent or queue

Then when an agent replies, your system sends the response back through the SMS API.

5) Set up agent workflows

Decide how your team will handle messages:

• Business hours and auto-replies
• Routing by queue, topic, or language
• Escalation rules
• Templates/macros for common replies
• Conversation ownership to avoid duplicate responses

6) Handle opt-in and compliance

This is important.

Make sure customers consent to receive SMS:

• Web forms, checkout flow, “text us” buttons, keyword opt-in, etc.
• Provide a clear disclosure about message frequency and data rates
• Include STOP to opt out, HELP for assistance

Also consider:

• TCPA in the US
• GDPR and local privacy laws
• Country-specific SMS regulations
• Quiet hours and messaging restrictions

7) Test the full loop

Before launch, test:

• Customer sends SMS
• Message appears in your system
• Agent replies
• Customer receives reply
• STOP/HELP keywords work
• Missed message and after-hours behavior

8) Monitor and improve

Track:

• First response time
• Resolution time
• Response volume
• Opt-out rate
• CSAT
• Peak hours and staffing needs

Simple architecture

A common setup looks like this:

Customer SMS → SMS Provider → Webhook → Support Inbox/CRM → Agent Reply → SMS Provider → Customer

If you want the easiest path

For most businesses, the quickest setup is:

1. Buy a texting-enabled number from Twilio or a helpdesk provider
2. Turn on a shared inbox
3. Register for compliance where required
4. Add an auto-reply and business hours
5. Train agents to respond from the inbox

If you want, I can also help with:

• A Twilio setup guide
• A Zendesk/Freshdesk setup
• A custom API/webhook example
• Compliance checklist for your country
• Recommendations based on your team size and volume