Reviews, Changelog & Documentation

BlueSteam Web Hosting

www.BlueSteam.net

We have been using the SMS addon for some time now and it has completely turned our business around. Providing SMS support to our clients and keeping them informed has improved our support response times ten fold. WHMCSnow has built an amazingly easy to use and feature rich SMS addon and their support is top notch! I can't believe I ran my business for 6years without this addon. Thanks WHMCSnow :)

Cemty LLC

www.cf.ee

To be the best, we only partnership with the best. SMS addon is something that catched our eyes.

Ravatech

www.RavaTech.net

Using WHMCS SMS Addon was an excellent choose to expand our communication with clients. Now our clients know when a password was changed, a domain is near to expire or a bill was generated. Are amazing see the confirmation texts they get to their phone. This Addon have continuous support and improvements. Thanks Daniel for this good idea.

OsemSpace

www.OsemSpace.com

You guys are rock! We have receive so much positive feedback since we use The SMS Addon. Expand our communication with clients. Are amazing to see the confirmation texts they get to their phone anytime anywhere. Really efficient. Good job Daniel!

Alex England

www.MindSystems.com.au

The SMS Addon has been on tremendous value to our business. Because Australia is in a different timezone to Europe and North America, SMS communication has proven a very useful and cheap way to keep our international clients informed. The feedback from our clients has been great, they love the added dimension of service. Dealing with WHMCSnow has been fantastic, they make the process quick and easy to understand and the actual addon has a much more professional finish to it that some others we have seen. Nice job!

v6.0.0 Latest	Released on 26^th October 2026 Redesigned the addon with a modern, mobile-friendly interface and updated dashboard widget. Added French, German and Spanish interface languages, with updated Arabic translations. Added campaign scheduling, cancellation and queue monitoring. Added resend from message history and improved existing support diagnostics. Added client mobile number verification and an optional verification notice. Added remaining invoice balance {balance}, payment failure, card expiry and service termination notifications. Added Plivo, Telnyx, BulkSMS and FireText gateways with delivery callbacks. Updated Clickatell and simplified the Twilio integration. Improved Admin Secure and SMS two-factor authentication. Fixed message signatures, older template formatting and various compatibility issues.
v5.1.8	Released on 8^th June 2025 PHP 8.3 Support
v5.1.7	Released on 22^nd May 2024 Added support for ionCube Loader v13 and PHP 8.2 Update notifications now shown in admin area
v5.1.6	Released on 20^th September 2023 Bug fixes
v5.1.5	Released on 7^th July 2023 Issue with Mass SMS resolved
v5.1.4	Released on 14^th November 2022 Added support for ionCube Loader v12 and PHP 8.1
v5.1.3	Released on 26^th September 2022 AddTransaction Hook added Logging system update Ability to disable Automatic Customer Country Code
v5.1.2	Released on 10^th July 2022 Bug Fixed “Notify field” Override issue fixed
v5.1.1	Released on 24^th June 2022 Bug Fixed Signature New Line Issue Fixed Bug Fixed Issue where possible to lose settings fixed
v5.1.0	Released on 30^th May 2022 SMS logging improvement Styling updates New SMS signatures Updated Client search improved New Requirement for “Notify field” removed Bug Fixed General bug fixes
v5.0.9	Released on 17^th May 2019 Fixed issue with Grace Period in the licensing system
v5.0.8	Released on 3^rd June 2018 Removal of mcrypt encryption in replacement to OpenSSL
v5.0.7	Released on 17^th April 2018 PHP 7.1 & 7.2 Support
v5.0.6	Released on 2^nd August 2017 Global SMS Tags now allowed on Admin actions
v5.0.5	Released on 25^th June 2017 Bug fixes {subtotal} SMS Tag added to invoices
v5.0.3	Released on 20^th February 2017 Now supports built in WHMCS' client phone number Legacy updater images removed in favour of FontAwesome Bug fixes
v5.0.2	Released on 17^th February 2017 Bug fixes
v5.0.1	Released on 15^th February 2017 Empty settings are no longer saved to database, saving storage and parsing performance Default SMS gateway defined if none set and only single SMS gateway active AJAX cache + log improvements ROOTDIR set for SMS proxy v4 -> v5 gateway migration issues fixed
v5.0.0	Released on 9^th February 2017 New Enable multiple SMS gateway support Updated Advance client country code lookup service Huge code improvements Styling improvements New Test API settings button New 2FA Custom codes / length / expiry (#937997) New Clear SMS logs (#419252) Updated Improved advanced logging and securely send to WHMCSnow support Updated Auto update speed/performance increase
v4.0.13	Released on 2^nd January 2017 Support for PHP 7
v4.0.12	Released on 21^st March 2016 New Send SMS directly from Client Summary page New Admin Ticket Flagged hook added - Get notified when a ticket is assigned to you Updated Certain client actions removed from "Safe Times" (Client Registration, Client Password Change) New More advanced logging and securely send to WHMCSnow support Bug Fixed Automatic unicode added to Two-Factor Authentication Bug Fixed Bug fixed when gateway API returns credit balance of "0"
v4.0.11	Released on 30^th January 2016 Now parses cron's Option Flags to disable SMS's for unneeded duplicate messages Invoice Paid - Now uses "Display Name" instead of shortcode in {paymentgateway} SMS tag Mass SMS - Global SMS tags added to customise bulk messages
v4.0.9	Released on 24^th November 2015 Updated Safe Times: SMS scheduling, never wake a client up in the middle of the night!
v4.0.5	Released on 28^th July 2015 Support for WHMCS v6 Improved automatic country code prefixing
v4.0.0	Released on 18^th November 2014 Code Improvements UI Improvements Automatic 1-Click Updates SMS API - Integrate the SMS Addon directly into your own script with a few line of code! Safe Times: Automatic SMS Scheduling so you do not wake a client up! API Callbacks: Keep your SMS logs up to date Automatic Unicode UPDATED: Mass Mail - Now create filters (the same as WHMCS' Mass Mail Tool) AJAX search added to Send SMS - Search Client Name, Company, Phone or Email NEW: Admin Secure - Two-Factor Authentication New Client and Admin hooks added Automatic Client Country Codes Additional SMS Tags Added Easier to Setup
v3.0.4	Released on 21^st September 2014 Bug Fixed Clickatell SenderID issue resolved - When using spaces Bug Fixed Workaround for WHMCS login on Invoice Due Dates
v3.0.3	Released on 8^th February 2014 Hot fixes
v3.0.0	Released on 27^th June 2012 Clickatell and SMS Global add-on's merged together GUI Improvements Global tag support added Ability to format date tag Client selection tidy up Improved logging system Improved unicode integration More actions Administrator actions now available Improved debugging system New database structure Improved licensing functions Version checker + updater SMS statistics + Widget Introduction of Admin Secure
v2.1.0	Released on 9^th April 2012 Mobile number input verification Style updates Bug fixes
v2.0.1	Released on 2^nd March 2012 Licensing Bug fixed Few general improvements
v2.0.0	Released on 28^th January 2012 Unicode Support (experimental) Tag Support, eg. {firstname} SMS messages for Invoice Reminder and Invoice Overdue Recode for new addon module system
v1.0.0	Released on 12^th April 2010 Initial Release

Getting Started

Installation / Upgrading

Back up your WHMCS files and database before installing or upgrading.

Extract the download and upload its contents into the WHMCS root, preserving the directory structure. The package includes modules/addons/sms_addon, modules/widgets/sms_addon.php, modules/security/sms2fact/sms2fact.php and includes/whmcsnowcore.php.
Open System Settings > Addon Modules (Setup > Addon Modules on older installations), activate The SMS Addon and allow the administrator roles that should access it.
Open Addons > The SMS Addon and activate your licence. Admin Secure features require the corresponding licence entitlement.
Open Settings > All Gateways, enable a gateway, enter its credentials under Active Gateways and save. Assign the countries it should handle, including a default route.
Review General Settings and enable only the notification actions you want. Personalise each message using its available tags.
Verify a test message before enabling customer notifications. The Debugger gateway can test the workflow without sending a real SMS.

Use the PHP version supported by your WHMCS installation and a compatible ionCube Loader. cURL, JSON, OpenSSL and database support must be available. Allow outbound HTTPS to your gateway and WHMCSnow licensing server.

Upgrading
Back up your files and database, then upload the new package over the existing addon files. Do not deactivate and delete the addon to upgrade it.
The addon applies its storage upgrades when required. Existing gateway settings, custom messages and deliberately blank templates are preserved. New notification types start disabled. Review them in Settings after upgrading.
The new queue stores scheduled send times and avoids automatic retries when provider acceptance is uncertain. Check the Queue page after upgrading. Keep your normal WHMCS system cron working.
Automatic updates use your existing WHMCSnow licensing and update system. Do not run an automatic update on a development installation that must retain unencoded source files.

Initial Setup

Enable a gateway under All Gateways. Configure its credentials and country routing under Active Gateways, then save settings. Gateway credentials are encrypted in the database and masked after saving.
Assign country-specific routes as needed and choose one default gateway for all other destinations. A manual send can explicitly select a gateway; automatic routing uses the client’s country where available. Avoid assigning the same country to several gateways.
Check Connection is available where the gateway supports a balance or account check. A successful check does not guarantee delivery to every country or sender ID. Send one test to an authorised number and check the result.
Scheduling is handled by the addon queue, so it does not depend on a gateway’s own scheduling feature.

Custom Client Fields

Under Settings > General Settings, choose the field containing the client mobile number. You can use WHMCS’ phone-number field or a suitable client custom field.
Store numbers in international format, for example +447700900123. Automatic Country Code Prefix can help with national-format numbers when the client country is correct.
To respect client preferences, select your notification custom field and the value that means the client has agreed to receive SMS. The “Just Send” option bypasses this field filter; use it only where appropriate for your notification setup.
If you require a client custom field during registration, mark it Required Field in WHMCS. Test with a client who has both a saved mobile number and the expected preference value. Changing these settings does not collect consent on your behalf.

Addon Settings

Open Settings to configure gateway accounts, country routing and general preferences. Client Actions and Admin Actions control which events send messages. Admin Secure contains licensed authentication, IP monitoring and directory-rotation features.

Choose the mobile number and notification preference fields carefully. Set a signature, history retention and domain renewal reminder intervals. Safe Times limits ordinary client notifications to the chosen hours; security alerts send immediately. Click Save Settings after making changes.

The administration interface follows the administrator’s WHMCS My Account > Language setting. English, Arabic, French, German and Spanish interface files are included. Missing translations fall back to English. Arabic uses a right-to-left addon layout.
The mobile-verification page follows the client page language. Provider-specific settings and gateway responses may remain in the provider’s original wording.
SMS templates are separate from the interface language. In Client Actions, use Languages to edit the templates for the client languages you use. Changing an administrator’s language does not translate or overwrite saved SMS messages. Keep placeholder names, such as {firstname}, unchanged.

Cron File

Normal outgoing notifications and campaigns are processed through the existing WHMCS system cron using the addon’s AfterCronJob hook. Keep the normal WHMCS cron running at the interval recommended for your WHMCS version; no additional SMS cron is required for normal operation.
Future scheduled messages remain waiting until due. Queue health shows due messages, scheduled messages, the oldest due message and the last completed check. It warns when no check has completed for 24 hours, messages are overdue or uncertain/interrupted sends require review.
Security notifications, including verification/2FA codes, password changes and new administrator IP alerts, send immediately and bypass the normal queue and quiet hours. They still require the corresponding action, licence entitlement and gateway configuration.
An interrupted or uncertain send is not automatically retried. Check the provider first to avoid duplicate SMS charges.

Features

SMS Tags

Tags are a new feature of the addon, This allow you to personalise the SMS even more with client details.
The following tags are included in the module, each action has there own tags assigned to them.

Action	Tags
Global Tags	{fullname} {firstname} {lastname} {clientemail}
Client Registration	{password}
Password Change	{newpassword}
Invoice Created	{invoiceid} {total} {datecreated} {datedue} {currency_prefix} {currency_suffix}
Invoice Paid	{invoiceid} {paymentmethod} {total} {datecreated} {datepaid} {currency_prefix} {currency_suffix}
Invoice Reminder Invoice Overdue	{invoiceid} {datecreated} {datedue} {total} {currency_prefix} {currency_suffix}
Module Created Module Unsuspend Module Password Change	{serviceid} {domain} {username} {password}
Module Suspend	{serviceid} {domain} {username} {password} {suspendreason}
Domain Registration Domain Transfer Domain Renewal	{domain} {registrar} {regperiod}
Domain Renewal Notices	{domain} {expiredays} {duedate}
Support Ticket Opened Support Ticket Reply	{ticketid} {ticketref} {subject} {message} {deptname} {priority} {status}
New Order Received	{orderid} {ordernumber} {totaldue}
Fraud Order	{orderid}
Cancellation Request Admin Cancellation Request	{type} {reason}
Affiliate Activation	{affiliatelink}
Two-Factor Authentication	{twofactor}
Domain Registration Failed Domain Transfer Failed Domain Renewal Failed	{domain} {registrar} {regperiod} {error}
Admin Secure-New Admin IP	{ip} {admin}
Admin Secure-New Admin Directory	{newadmindir}
Support Ticket Flagged	{ticketid} {ticketref} {subject} {priority} {status}

SMS Addon 6.0.0 additions
Enable each action you want under Client Actions or Admin Actions, then edit its message. Available tags lists placeholders supported by that action; click a tag to insert it into the selected message field.
Invoice messages include {balance} for the remaining invoice balance. Payment-failure and card-expiry actions can be configured independently. Service-termination notifications are available alongside creation, suspension and unsuspension actions.
Client templates can be configured for multiple languages. English defaults are supplied for supported actions, but existing customised or deliberately blank templates are preserved on upgrade. Newly added actions start disabled.
Do not assume a tag from one action is available in another. Avoid including secrets in messages unless you deliberately require that legacy action.

New and updated tags

Invoice events: {balance} is the remaining invoice balance.
Service termination: {serviceid} and {domain}, alongside the shared client name/email tags.
Campaigns: {firstname}, {lastname}, {fullname}, {clientemail}.

Client Profile Intergration

Enable Client Mobile verification in General Settings to show a notice at the top of client pages until the saved number is verified. The verification page is index.php?m=sms_addon within your WHMCS installation and requires the client to sign in.
The client requests a code, receives it immediately by SMS and enters it on the page. Codes expire, are single-use and allow a limited number of attempts. Requests have a five-minute cooldown and daily limit.
Verification applies to the saved number. Changing it requires verification again. Disabling the setting hides the notice and the administration-profile verification badge; it does not erase the existing verification record.
Verification proves access to a mobile number. It is separate from permission to send marketing or optional notifications.

Administrators can also send a message from the client summary page. The saved mobile number and verification state are shown when client mobile verification is enabled.

Interface languages and message templates

The administration interface follows the administrator’s WHMCS My Account > Language setting. English, Arabic, French, German and Spanish interface files are included. Missing translations fall back to English. Arabic uses a right-to-left addon layout.
The mobile-verification page follows the client page language. Provider-specific settings and gateway responses may remain in the provider’s original wording.
SMS templates are separate from the interface language. In Client Actions, use Languages to edit the templates for the client languages you use. Changing an administrator’s language does not translate or overwrite saved SMS messages. Keep placeholder names, such as {firstname}, unchanged.

Manual messages, history and resend

Use Send SMS to search for a client or enter international mobile numbers. Choose automatic routing or a specific active gateway. Review the segment count before queueing the message.
Messages provides search, period and status filters. View message opens the saved body, gateway response and provider reference. Resend message queues the saved message to the same recipient using current routing and preserves the original signature once.
Authentication and password-bearing messages cannot be resent from history. Authentication message contents are omitted from the saved log. History retention controls how long message records are kept; choose Keep history if you do not want automatic removal.

Campaigns: recipients, scheduling and cancellation

Choose Clients, Product or service, Product addon or Domain, then set your filters. Recipient matches update while you change the filters. Leave a selection empty where the page allows all values.
Write the message and insert the available name/email placeholders. The preview and segment estimates help you review the audience; personalisation can change the final length.
Choose As soon as possible or a scheduled date and time in the website/server timezone shown on the page. Review the campaign before queueing it. The addon rechecks eligible recipients and excludes invalid numbers or clients who have opted out.
Queue shows campaign progress. Cancel campaign cancels messages still waiting. Messages already being sent or accepted by a provider cannot be recalled. Duplicate-submission protection prevents the same review request from queueing the campaign twice.

SMS parts, Unicode and signatures

A long text can be billed as several SMS parts. GSM messages usually allow 160 characters in one part or 153 per part when combined. Unicode messages usually allow 70 characters in one part or 67 per combined part. Some GSM extension characters take two character positions.
The addon estimates parts including your configured signature. Personalised client details can change the final length, and the provider determines billing. Confirm the provider’s limits and pricing.
The signature is added to new messages. Resending a saved message preserves its saved text and does not append the signature a second time.

SMS API's

Clickatell

Use Clickatell for a current Clickatell Portal account and Clickatell Legacy only for the older username/password/API-ID integration. The current driver uses Basic HTTP API, not One API.

In Clickatell Portal, open My Workspace > SMS > New SMS Setup. Choose API, then the appropriate one-way or two-way setup for your destinations. A one-way setup does not support US recipients.
Choose Basic HTTP API and create an HTTP API integration. Start in Sandbox. Standard is suitable for general notifications and campaigns; do not use a priority transactional route for marketing.
Enable account fraud protection and allow the hosting server’s actual outbound public IP. This can differ from your website IP or home/VPN address.
Enable Delivery Notifications, choose POST, and paste the full private Delivery callback URL shown under SMS Addon > Settings > Active Gateways > Clickatell. Keep the callback token private.
Allow enough message parts for your templates. Parts are separately billable SMS segments. Leave phone-number conversion disabled when submitting full international numbers.
Copy the API Key into Clickatell’s API Key field in the addon. Leave From blank unless your sender has been approved for the destination.
Add and verify a sandbox test number in Clickatell. Keep a positive balance if the portal requires it. Send a test through the addon and confirm handset receipt and Delivered status.
When ready for paid traffic, change the integration to Production and save. Assign the default/country routes in the addon and remove overlapping routes from the old gateway.

The internal gateway and callback filenames remain clickatell_new for compatibility. “Accepted” means the provider accepted the request; “Delivered” requires a delivery receipt. Provider account requirements and destination restrictions can change; check the current Clickatell portal guidance.

SMS Global

Plivo, Telnyx, BulkSMS and FireText

These gateways use the same single-file gateway interface as the existing integrations, with shared transport and callback helpers. No separate gateway SDK folder is required.

Plivo: enter your Auth ID, Auth Token and permitted sender. The authenticated callback URL is included automatically when sending.
Telnyx: enter your API key, sender and messaging profile where required. The authenticated callback URL is included automatically when sending.
BulkSMS: enter your API token ID and secret. Configure the private addon callback URL in your provider’s webhook settings for sent-message status reports.
FireText: enter your API key and sender. Configure the private addon callback URL in your FireText delivery-report settings.

Copy callback URLs from Active Gateways rather than constructing them yourself. Your WHMCS System URL must use HTTPS and be reachable by the provider. Sender registration, number ownership, destination permissions and account approval remain provider requirements.
Use a real provider test to confirm end-to-end delivery. Debugger results test addon behaviour, not carrier delivery.

Delivery receipts and message statuses

The gateway must support delivery reports and have them configured for the addon to receive final delivery status. Keep the full authenticated callback URL private.

Queued: waiting for the local worker or provider processing.
Accepted: the provider accepted the send request; this does not prove handset delivery.
Delivered: an explicit delivery receipt was received.
Failed: the request or delivery failed.
Unknown: acceptance could not be confirmed. Check the provider before sending again, because the message may already have been accepted.

New callback handlers match both gateway and provider reference and protect final receipts against late progress updates. Callbacks do not automatically resend messages. A firewall, invalid callback URL or restrictive security rule can prevent delivery reports even when the SMS arrives.

Admin Secure

SMS two-factor authentication

Admin Secure requires its licence entitlement. Configure the administrator mobile numbers and an active gateway before enabling SMS authentication.
Open WHMCS authentication settings from Settings > Admin Secure > Manage authentication. Make the SMS authentication module available for administrators and/or clients as appropriate. Each user then enrols through their own account’s security settings.
Save the WHMCS backup code privately during enrolment. To recover access without the phone, use Login using Backup Code and save the replacement code shown by WHMCS. Backup codes are single-use.
SMS codes send immediately, expire and have attempt limits. Refreshing the challenge does not send a new code automatically. Test login and recovery before requiring 2FA for other users.

IP alerts and administrator directory rotation

Admin Secure can notify you about new administrator IP addresses and changes to the administration directory. Review trusted administrator IPs and CIDR ranges before enabling monitoring. Security alerts send immediately.
Automatic directory rotation requires the WHMCS configuration file to be writable and a suitable word pack. Set the interval and word-use preference carefully, and keep a backup and server access available.
Review any web-server restrictions, bookmarks, integrations or monitoring tied to the admin URL before using directory rotation. If a change cannot be completed safely, the addon attempts to retain or restore the previous directory configuration.

Troubleshooting

Testing with the Debugger gateway

Debugger simulates gateway outcomes and sends a diagnostic email through WHMCS instead of contacting an SMS carrier. Configure its recipient address, select it explicitly and use a test client/number.
It can exercise accepted, delivered, rejected and uncertain outcomes, along with queue processing, templates and signatures. Use isolated tests when checking expiry, incorrect codes or changing numbers.
A successful Debugger email verifies the addon workflow and mail handoff. It does not prove that a real provider accepts your credentials, that a sender is approved, or that carrier callbacks reach your site. Always finish gateway setup with an authorised real SMS test.

Diagnosing failed or uncertain messages

Open the message details and compare its reference and response with your provider dashboard. Check credentials, balance, sender approval, destination permissions, international number format and country routing.
For queued messages, check the WHMCS cron and Queue health. For a missing Delivered status, check provider callback settings, HTTPS reachability and firewall rules.
If status is Unknown or sending was interrupted, check the provider before resending. The addon avoids automatically retrying a request that may already have been accepted.
Support diagnostics in the message dialog can send the selected message and redacted diagnostics to an existing WHMCSnow support ticket. Review what you are sharing and never publish API keys or private callback URLs.

Survey + Testimonial Addon

Staff Wiki / Knowledgebase

File Monitor

TicketShield

WHMCS Go

Password Safe

SMS notifications for WHMCS

Client notifications

Campaigns and message history

Supported gateways

Admin Secure for WHMCS

Multilingual interface

Screenshots

Overview

Send SMS

Campaigns

Messages

Active Gateways

General Settings

Client Actions

Admin Actions

Admin Secure

Client Mobile Verification

Dashboard Widget

Two-Factor Authentication

Queue

Multilingual

Reviews, Changelog & Documentation

BlueSteam Web Hosting

www.BlueSteam.net

Cemty LLC

www.cf.ee

Ravatech

www.RavaTech.net

OsemSpace

www.OsemSpace.com

Alex England

www.MindSystems.com.au

v6.0.0

v5.1.8

v5.1.7

v5.1.6

v5.1.5

v5.1.4

v5.1.3

v5.1.2

v5.1.1

v5.1.0

v5.0.9

v5.0.8

v5.0.7

v5.0.6

v5.0.5

v5.0.3

v5.0.2

v5.0.1

v5.0.0

v4.0.13

v4.0.12

v4.0.11

v4.0.9

v4.0.5

v4.0.0

v3.0.4

v3.0.3

v3.0.0

v2.1.0

v2.0.1

v2.0.0

v1.0.0

Getting Started

Features

SMS API's

Admin Secure

Troubleshooting

Getting Started

Installation / Upgrading

Initial Setup

Custom Client Fields

Addon Settings