WooCommerce SMS and WhatsApp Plugin With WordPress OTP Login

The free Fast2SMS plugin for WordPress and WooCommerce adds mobile OTP login, signup verification, COD order verification and order notifications on SMS and WhatsApp to your store, with no coding. You install it from WordPress.org, paste your Fast2SMS API key, switch on the features you want and pay only per message from your Fast2SMS wallet. For lead capture, the Fast2SMS popup lead form collects visitor mobile numbers and email IDs, and verifies Indian numbers with OTP.

This guide is for Indian store owners, bloggers and agencies who run WordPress. It explains each feature in plain words, shows the real setup screens, covers the DLT and WhatsApp template rules you must follow in India, lists what each message costs, and ends with message examples and fixes for common problems.

What the free Fast2SMS plugin does

WordPress powers a huge share of Indian small business websites, and WooCommerce turns many of them into stores. Both are excellent at pages and products, but neither sends SMS or WhatsApp messages on its own. Out of the box, a WooCommerce store emails the customer, and in India many shoppers never open those emails. The official Fast2SMS plugin connects your site to the bulk SMS, OTP SMS and WhatsApp Business API services of your Fast2SMS account, so the right message reaches the customer’s phone at the right moment.

The plugin covers these jobs:

• OTP login. Customers log in with their mobile number and a fresh one time password, on the WooCommerce My Account page or on any page where you place the plugin shortcode. No password to remember, no reset emails.
• Signup verification. New users must verify their number with an OTP before the account is created. The verified number is saved to the customer profile.
• COD verification. Cash on Delivery customers receive an OTP confirmation link, and verified orders get a badge in your WooCommerce orders list.
• Order notifications on SMS and WhatsApp. Order confirmations and status updates go out automatically, using your own sender ID and approved templates.
• Bulk campaigns. Send SMS or WhatsApp campaigns to your customers from the WordPress dashboard.
• Form OTP. Verify mobile numbers on Contact Form 7, WPForms and Elementor forms.
• WhatsApp two-factor authentication. Add a WhatsApp code as a second step for WordPress logins.
• Smart OTP channel choice. Codes can go on SMS or WhatsApp, with automatic fallback to the other channel when the first one fails.

Some features work on any WordPress site and some need WooCommerce. OTP login and signup verification work on plain WordPress too. COD verification and order notifications need WooCommerce, because they depend on WooCommerce orders. The help guide on WordPress vs WooCommerce notifications and OTP shows the full split.

Separately, Fast2SMS has a WordPress popup plugin, the F2 Popup Lead Form, for collecting visitor email IDs and mobile numbers through popups, sidebar forms and in-post forms. It is covered in its own section below, because many site owners use it for lead generation even when they do not run a store.

All Fast2SMS plugins are free. You can see every ready-made integration, including Shopify and TallyPrime, on the Fast2SMS integrations page.

Why Indian stores need OTP and SMS or WhatsApp alerts

A wrong mobile number looks harmless when it is typed. It becomes expensive later. Order updates go nowhere, the delivery rider cannot reach the customer, and a COD parcel often comes back after you have paid shipping both ways. India runs on cash on delivery more than most markets, so this problem hits Indian stores harder than stores elsewhere.

• Fake and mistyped numbers. One OTP at signup or on a COD order confirms a real, reachable person before the parcel leaves your warehouse.
• Bot and coupon abuse. An offer like “first order 50% off” invites one person with ten fake accounts. A bot cannot receive a code on a real Indian mobile number, and every extra account now needs a real SIM.
• Password pain. Customers forget passwords and stop at the login page. With OTP login, the phone becomes the key.
• Silent customers. Shoppers who get no update after paying start calling or writing to you. A confirmation message and a shipping update answer the question before it is asked.

What you need before you start

• A WordPress website. For order features, WooCommerce installed and active.
• Admin access to WordPress so you can install plugins.
• A free Fast2SMS account. Signup at fast2sms.com gives you ₹50 free credit to test, and you can recharge from ₹100 later.
• Your Fast2SMS API key, found in the Dev API section of the panel.
• For SMS: DLT registration with an approved sender ID and approved content templates. This is a TRAI rule for business SMS in India. Fast2SMS helps with DLT registration for free.
• For WhatsApp: a WhatsApp Business number connected to Fast2SMS through the official Meta Cloud API, and templates approved by Meta. Connecting a new number, or your existing WhatsApp Business app number, is free with no monthly fee.

Step 1: Install the plugin and connect your API key

1. Install the plugin. In your WordPress admin, go to Plugins > Add New, search for “Fast2SMS”, click Install Now and then Activate. You can also download it from the Fast2SMS plugin page on WordPress.org and upload the zip under Plugins > Add New > Upload Plugin.
2. Copy your API key. Log in to your Fast2SMS panel and open Dev API. Copy the key shown there. The same key works for every Fast2SMS integration and for the REST API.
3. Paste and validate. Open the Fast2SMS plugin settings in WordPress, paste the API key and validate it. Once it is accepted, the plugin can send messages from your account.

Step 2: Create your OTP ID in Smart OTP

The plugin does not decide by itself whether a code goes on SMS or WhatsApp. That choice lives in your Fast2SMS panel, in the Smart OTP section, as an OTP ID. One OTP ID holds the channel, the template, the sender and the fallback setting.

1. In the Fast2SMS panel, open Smart OTP and add an OTP template.
2. Pick the primary channel. For WhatsApp, choose your approved authentication template. For SMS, choose your DLT-approved OTP template, sender ID and entity.
3. Set up the fallback on the other channel if you want one. If the primary channel fails, the same code goes out on the second channel automatically.
4. Copy the OTP ID and paste it into the plugin.

The big advantage of this design: you can change the channel or the fallback later in the panel, and your WordPress site follows instantly, with no plugin change. Fast2SMS generates, sends, expires and checks every code on its own servers, so your WordPress database never stores an OTP. Customers can ask for the code again within a 10 minute resend window. The Smart OTP guide explains the full flow.

Step 3: Turn on OTP at signup, login and COD checkout

Open the OTP & Login tab of the plugin. Each verification point has its own switch, so you can start with one and add the others later:

1. Registration verification. New customers verify their mobile number with an OTP before WordPress creates the account. No verified number, no account, which is where bots stop.
2. OTP login. Customers log in with their verified number and a fresh code on the My Account page, or on any page where you add the plugin shortcode.
3. COD verification. Every Cash on Delivery customer receives an OTP confirmation link. Details are in the COD section.
4. Run the built-in test. The same tab has an end-to-end test, so you can send yourself a real code and check the whole flow before customers see it.

What the customer sees at signup

The registration form asks for the mobile number. The customer taps to get a code, types it in, and only then is the account created. The verified number is saved to the profile, ready for order updates later.

What the customer sees at login

On the WooCommerce My Account page, the customer enters the mobile number, receives the code on SMS or WhatsApp (whichever your OTP ID uses), types it and is logged in. If WhatsApp is the channel, the message shows your verified business name and a Copy code button, which makes entry quick on mobile.

Existing customers and abuse limits

Turning on OTP does not lock out old customers. Customers without a verified number keep logging in as before, and the plugin also matches numbers from their past orders. Verification applies only where you switch it on. To stop people from requesting codes again and again, the plugin has its own per-phone and per-IP limits with a visible cooldown timer.

For a deeper look at each option, see the help guides on WooCommerce OTP verification, WooCommerce OTP login and free OTP login for WordPress.

COD verification and lower RTO

Return to origin (RTO) is the quiet profit killer for Indian stores. A COD order placed with a fake or unreachable number is packed, shipped, refused or never delivered, and shipped back. You pay for both journeys and the stock sits blocked for days.

With COD verification switched on, every COD customer receives an OTP confirmation link right after placing the order. When the customer confirms, the order gets a verified badge in your WooCommerce orders list. The plugin does not cancel unverified orders. It marks them, and you decide what to do: ship, call first or hold.

A practical routine many store owners follow: every morning, filter COD orders, pack the verified ones first, and give the unverified ones a quick call. Verified numbers also make every later message, such as shipping updates and delivery calls, more likely to reach the buyer. The help guide on WooCommerce COD OTP verification and the one on COD to prepaid and pending payment reminders go further.

Order notifications on SMS and WhatsApp

Order notifications are the messages customers actually expect: “your order is confirmed”, “your order has shipped”, “your order is delivered”. The Fast2SMS plugin sends order confirmations and status updates from your WooCommerce store automatically. For each message you pick the channel, the sender ID and the approved template you want to use.

SMS or WhatsApp: which one for order updates?

Most stores use both: WhatsApp as the main channel for order updates because customers read it and see the business name, and SMS where WhatsApp is not available. If you prefer WhatsApp, the WooCommerce WhatsApp notifications guide shows the setup in detail, and the order status SMS and WhatsApp guide explains what to send at each status.

Abandoned carts and back in stock

Order notifications work best on verified numbers, and so do recovery messages. Abandoned cart reminders on WhatsApp and SMS bring back shoppers who left before paying. See the help guides on abandoned cart recovery on WhatsApp and SMS and the back in stock notifier for how stores use them. Offers and discount messages are promotional, so send them only to customers who agreed to hear from you, and use the matching template category.

Form OTP and WhatsApp two-factor login

Not every WordPress site sells products. Coaching institutes, clinics, real estate agents and service companies collect enquiries through forms, and fake numbers in those forms waste sales calls. The Fast2SMS plugin adds OTP verification to forms built with Contact Form 7, WPForms and Elementor, so an enquiry reaches you only with a mobile number that has been verified.

For site security, the plugin also supports WhatsApp two-factor authentication. After the normal username and password, the user confirms a code sent on WhatsApp. It is a simple way to protect admin and editor accounts, which are the accounts attackers usually try first. The guides on WhatsApp two-factor authentication for WordPress and WhatsApp OTP for WordPress walk through both.

Bulk SMS and WhatsApp campaigns from WordPress

Once your customers are verified, your list becomes valuable. The plugin lets you send bulk SMS and WhatsApp campaigns from the WordPress dashboard, so you do not have to export customers to a spreadsheet every time you announce a sale or a new collection. Promotional SMS must use a promotional DLT template, and WhatsApp campaigns use Meta-approved marketing templates.

For bigger campaigns, the Fast2SMS panel itself offers bulk sending with Excel upload, scheduling and delivery reports. See bulk SMS from WordPress, WooCommerce SMS marketing campaigns and our guide to bulk WhatsApp messages.

WordPress popup lead form: collect visitor mobile numbers and emails

Most visitors leave a website without buying or enquiring. A good popup gives them one easy reason to share a mobile number or email first: a discount, a newsletter, a free guide or a callback. Fast2SMS built the F2 Popup Lead Form plugin for exactly this. It collects visitor email IDs and mobile numbers through popups, sidebar widgets and forms inside posts and pages, and it can verify Indian mobile numbers with OTP so the leads you collect are real. No coding is needed.

What the popup plugin can do

• Collect email IDs, mobile numbers or both. Choose to collect email only or mobile only if you want a shorter form.
• Verify Indian mobile numbers with OTP, and verify email addresses with OTP for visitors from any country.
• Collect non-Indian mobile numbers without verification. Numbers from 200+ countries are supported.
• Save every lead in your own WordPress database.
• Change the popup and lead form heading, the thank you message and whether OTP verification is on.
• Premium popup designs that load fast.

Popup types you can build

The same plugin covers many common lead generation formats: email popup forms, mobile number popup forms, newsletter subscribe popups, lead gen popups, contact form popups, WooCommerce upsell popups, discount offer popups, and lead forms placed inside pages and posts.

Four ways to show the form

1. Open the popup lead form instantly when the page loads.
2. Open it after a two or five second delay, so visitors see your content first.
3. Create a shortcode and show the lead form on a specific page or post.
4. Create a shortcode and add the lead form to a sidebar widget.

How to install and set up the popup lead form

1. Log in to your WordPress admin.
2. Install “F2 Popup Lead Form” from WordPress.org through Plugins > Add New, or upload the downloaded zip file with Plugins > Add New > Upload Plugin.
3. Activate the plugin from the Plugins menu.
4. Open the popup settings and adjust the heading, trigger and fields to your need.
5. Choose what to collect: email only, mobile only or both, and whether to verify with OTP.
6. To show the form in the sidebar or on specific posts and pages, create a shortcode and paste it where you want the form.
7. To verify Indian mobile numbers with OTP, open the API settings page and connect your Fast2SMS API key.

Who uses it: business owners, bloggers, ecommerce sites, designers, developers and marketing agencies who want to grow their lists, leads and sales. Step-by-step help is in the guides on collecting visitor mobile numbers in WordPress, collecting visitor email IDs in WordPress and WordPress mobile OTP verification via the Fast2SMS plugin.

DLT and WhatsApp templates for WooCommerce

DLT basics for SMS

Every business SMS in India must follow DLT, a TRAI regulation. In short, you register three things on any operator’s DLT portal:

1. Entity: your business, registered once.
2. Header (sender ID): the six-character name your customers see, such as a short form of your brand.
3. Content templates: the exact text of each message, with variable slots for the parts that change, like name, order number or amount.

When the plugin sends an SMS, the text must match an approved template, otherwise the message is blocked. Fast2SMS gives free DLT support for entity registration, sender ID approval and template approval, plus ready sample templates. Start at DLT registration and use the ready DLT SMS templates for WooCommerce.

Variable tags in DLT templates

Newer DLT rules use typed variable tags with length limits. Choose the right tag for each slot:

The DLT variable tagging reference and the sample DLT templates show approved examples.

WhatsApp templates

WhatsApp business messages that start a conversation must use a template approved by Meta. Templates have a category: utility for order and delivery updates, authentication for OTPs, and marketing for offers and campaigns. The category decides the price, so write order updates as clean transaction messages without sales lines. Fast2SMS reviews your templates before you submit them to Meta, and connecting your WhatsApp Business number through the panel is free. Read more on the official WhatsApp Business API guide and the WhatsApp OTP API guide.

Message examples you can adapt

Short, specific and useful messages get read. Each example below has a DLT-style SMS version and a WhatsApp version. Replace BRAND with your store name and get each text approved before use.

Good habits for every message:

• Put the useful fact first: order number, amount or OTP.
• Use one link at most, and make sure it opens on mobile.
• Keep order updates free of sales lines, so they stay in the utility category on WhatsApp and the right DLT category on SMS.
• Never send OTPs in a promotional template, and never ask customers to share a code.
• Remember that a standard SMS has 160 characters (70 for Hindi and other Unicode text). Longer texts are sent in parts, and each part is charged as one SMS.

What it costs

The plugin is free to install and use, with no monthly fee and no setup charge. You pay only for messages, from the prepaid wallet in your Fast2SMS account. The same rates apply whether a message goes from the panel, the API or the plugin.

Between those two SMS slabs, the rate falls step by step as your recharge grows; the full table is on bulk SMS pricing. WhatsApp rates and what is included free are on WhatsApp pricing. A few points that matter for stores:

• WhatsApp messages are billed on delivery basis, and failed WhatsApp messages are refunded to your wallet automatically within 48 hours.
• Your wallet balance never expires. Only the discounted SMS rate of a bigger recharge has a validity.
• 18% GST applies on the recharge amount, with a GST invoice for every payment.
• New accounts get ₹50 free credit, enough to connect the plugin and send test messages.
• High volume? Rates are negotiable. Call sales on +91-6262778811 or book a free meeting.

A quick way to estimate: if your store gets 1,000 orders a month and sends three WhatsApp utility updates per order, that is 3,000 messages at ₹0.25, or ₹750 plus GST. Add the OTPs you expect at ₹0.25 each on WhatsApp, or at your SMS rate.

How to compare WooCommerce SMS and WhatsApp plugins

There are many SMS and WhatsApp plugins for WooCommerce. Some charge a monthly licence, some sell message credits inside the plugin, and some need a separate SMS provider. Rather than compare names, ask the same questions of every option:

For a wider view, see the help guides on the best WooCommerce SMS and WhatsApp plugins in India and WooCommerce OTP plugins compared.

Troubleshooting common problems

The API key is not accepted

Copy the key again from Dev API in the Fast2SMS panel, with no extra spaces at the start or end. If you regenerated the key recently, the old one stops working, so paste the new one.

The OTP is not received

• Check your wallet balance in the Fast2SMS panel.
• Check that the OTP ID in the plugin is correct and that its template is approved: a DLT OTP template for SMS, or an authentication template for WhatsApp.
• Add a fallback channel to the OTP ID, so a failed WhatsApp code goes on SMS, or the reverse.
• Ask the customer to wait for the cooldown timer before trying again. Repeated requests hit the plugin’s per-phone and per-IP limits.
• Look up the number in the delivery report of your panel to see the exact status.

More fixes are in the WooCommerce OTP not received guide.

SMS is blocked or rejected

Almost always a DLT mismatch. The text sent must match the approved template, including fixed words and spaces, and each variable must fit its tag. Compare the plugin template with the one approved on DLT, and check that the sender ID is linked to that template.

A WhatsApp message failed

The most common reasons are a number that is not on WhatsApp or a template that is not approved. Failed WhatsApp messages are refunded automatically. If the customer is not on WhatsApp, use SMS for that message.

The OTP login form does not show

Make sure the OTP login switch is on in the OTP & Login tab. If you use a page caching plugin, exclude the My Account, cart and checkout pages from the cache, as WooCommerce itself recommends, so visitors always see the live form.

Still stuck? Write to [email protected], call +91-6262778822, use the contact page or schedule a free meeting with the team. Developers can find every endpoint at docs.fast2sms.com.

Why store owners choose Fast2SMS

• Made by the provider. The plugin is built by Fast2SMS, which has run business messaging in India since 2011. No middleman, no markup.
• One account for every channel. SMS, WhatsApp, OTP, RCS and voice calls share one wallet and one API key.
• Pay per message. No monthly fee, no setup fee, no per-number fee.
• Reliable delivery. 99.9% uptime and Smart OTP fallback across two channels.
• Free help with compliance. DLT registration support and WhatsApp template review at no charge.
• Free tools included. WhatsApp live chat inbox, chatbot builder, webhooks and delivery reports come with every account.

If you also sell on Shopify, the Shopify SMS and WhatsApp guide covers the Fast2SMS Shopify app, and the Shopify vs WooCommerce guide compares the two for messaging. The complete plugin setup guide covers every setting in one place.