Approach A: Zoho CRM Native SMS Integration + Workflow Rule (Best for most businesses not on EU Datacenter)

What it does: Connects a supported SMS gateway inside Zoho CRM, then sends messages automatically through a Workflow Rule when a lead is created.

Step-by-step setup:

Step 1 — Choose a UK-capable SMS gateway

Zoho CRM’s SMS integration framework supports several providers, including Twilio, ClickSend, and SMS-Magic (Screen Magic). For UK businesses, consider:

• Twilio — strong UK coverage, alphanumeric sender IDs, long codes, and two-way messaging. It also offers delivery reporting.
• ClickSend — UK support, delivery reporting, and a straightforward API.
• SMS-Magic — conversation management and inbound handling, with separate licensing.

Before choosing a provider, confirm it supports:

• Workflow-triggered outbound SMS, not just manual sends
• Merge fields from CRM records
• Delivery status written back to Zoho
• Inbound STOP reply handling
• UK sender ID or long code availability
• Consent and suppression list synchronisation

Check the Zoho Marketplace for the current list of supported providers and their UK-specific capabilities, which can change.

Step 2 — Connect the gateway

In Zoho CRM, go to Setup → Channels → Business Messaging → SMS (the exact path may vary by UI version). Select your provider, enter your API credentials, and configure your sender ID or number.

Store API keys in Setup → Developer Space → Connections. Never hardcode them in functions.

Step 3 — Create your SMS template

In the SMS settings, create a template. Keep it under 160 characters to avoid message splitting (see the pitfalls section for details):

“Hi ${Leads.First Name}, thanks for getting in touch with [Business Name]. We’ll call you shortly. Reply STOP to opt out.”

Use "Hi there" when the first name is blank, rather than "Hi ,".

Step 4 — Build the Workflow Rule

Go to Setup → Automation → Workflow Rules → Create Rule:

• Module: Leads
• Trigger: Record Action → Create
• Conditions (recommended):
  • Mobile is not empty
  • SMS Opt-in equals True
  • Welcome SMS Sent equals False
• Instant Action: Send SMS (available once the integration is configured; it may be labelled “SMS Notifications”)
• Select: your template and the Mobile field

Edition note: Workflow Rules with custom actions typically require Zoho CRM Professional edition or above. Confirm your plan supports the workflow actions your gateway integration uses.

Step 5 — Test thoroughly

Create a dummy lead with your own mobile number. Check that the message arrives, the merge field populates correctly, and the activity appears on the lead timeline.

One-click manual SMS (within Approach A)

Once the integration is live, staff can open a lead record, click the SMS icon in the record header, select a template, and send. Some gateway integrations also support bulk sends from list view.

This still requires a template picker step. For a true single-click experience, combine it with Approach B.

Approach B: Custom Button + Deluge Function (Best for true one-click sending and EU Datacenter accounts)

What it does: A custom button on the Lead record runs a Deluge script that sends a fixed message through your gateway’s API. No popup or template selection is needed.

This is also the recommended route for EU Datacenter accounts, since it bypasses Zoho’s native SMS layer and calls the gateway API directly.

Step-by-step setup:

1. Go to Setup → Customization → Modules and Fields → Leads → Links & Buttons → New Button
2. Set placement to Record Detail Page (and optionally List View for bulk sends)
3. Set action to Write a Function (Deluge)

Your Deluge function should:

// Fetch lead details
leadId = input.get("leadId");
leadDetails = zoho.crm.getRecordById("Leads", leadId);

firstName = leadDetails.get("First_Name");
mobile = leadDetails.get("Mobile");

// Normalise UK number to E.164 format
// Converts 07123 456789 → +447123456789
if(mobile.startsWith("0"))
{
  mobile = "+44" + mobile.removeFirstOccurrence("0");
}
mobile = mobile.replaceAll(" ", "");

// Build message
if(firstName == null || firstName == "")
{
  firstName = "there";
}
message = "Hi " + firstName + ", thanks for contacting [Business]. We'll be in touch shortly. Reply STOP to opt out.";

// Call gateway API (example: Twilio)
params = map();
params.put("To", mobile);
params.put("From", "YourSenderID");
params.put("Body", message);

response = invokeurl
[
  url: "https://api.twilio.com/2010-04-01/Accounts/YOUR_ACCOUNT_SID/Messages.json"
  type: POST
  parameters: params
  connection: "twilio_connection"
];

// Log activity on lead
note = "Welcome SMS sent to " + mobile + " at " + zoho.currenttime;
zoho.crm.addNote("Leads", leadId, note, "SMS Activity");

// Update 'Welcome SMS Sent' field to prevent duplicates
updateMap = map();
updateMap.put("Welcome_SMS_Sent", true);
zoho.crm.updateRecord("Leads", leadId, updateMap);

For more on writing and troubleshooting Deluge functions, see our guides on Mastering Zoho Flow Custom Function Outputs and Master Deluge Troubleshooting.

Pro tip: Create separate buttons for different templates, such as “Missed Call SMS”, “Quote Follow-Up”, and “Booking Reminder”. Each can call the same function with a different message parameter.

Approach C: Zoho Flow or Make.com (Best when your gateway isn’t natively supported, or you’re connecting multiple apps)

What it does: A no-code flow triggers on “Lead Created” in Zoho CRM and calls an SMS provider, without custom code.

Setup in Zoho Flow:

1. Create a new flow with trigger: Zoho CRM → Lead Created
2. Add a filter: Mobile is not empty AND SMS Opt-in is True
3. Add an SMS action (Twilio, ClickSend, Vonage, etc.) or a webhook
4. Add a final step to update a CRM field: Welcome SMS Sent = Yes (prevents duplicates)

Alternatively, Make.com has a visual, drag-and-drop automation builder that connects Zoho CRM to virtually any SMS provider. It’s useful if you already use Make for other automations or your gateway isn’t in Zoho Flow’s native connector library.

For a walkthrough of connecting Zoho products through Flow, see our Step-by-Step Guide: Integrating Zoho SalesIQ with Zoho Creator via Zoho Flow.

For one-click manual sends via Approach C: You’ll still need a custom button (Approach B) to trigger the flow via webhook, rather than call the gateway directly.

Limitations: Zoho Flow has task and execution limits depending on your plan. Make.com is a separate subscription. Both add another system to monitor.

Approach D: Other Zoho Products (Situational)

Approach E: WhatsApp as a Complement (Longer-term consideration)

Zoho CRM integrates with the WhatsApp Business API. Template messages need Meta approval, and contacts must have opted in. Open rates are often higher than SMS, and per-message costs can be lower.

If your leads are likely to use WhatsApp, tools like Treble.ai can help you build WhatsApp messaging workflows around your CRM data. This won’t replace SMS if your audience doesn’t use WhatsApp, but it may fit into your longer-term communication strategy.