SMS opt-in methods reference

Learn about the different methods for growing your SMS list with Klaviyo.

By collecting SMS consent from these interested customers, you can send personalized and timely messages, such as order updates, exclusive promotions, and loyalty rewards, which can help you build a loyal customer base.

Best practices for collecting SMS consent

Remember that your entire audience is a potential SMS subscriber, from new site visitors to one-time customers, email subscribers, or social media followers. When collecting SMS consent, there are a few best practices to keep in mind to grow your audience and drive revenue:

• SMS must be optional and cannot appear to be required. To accomplish this, SMS consent should be collected separately from any other marketing channel.
  • As a general best practice, use a multi-step form if you’re asking for both email and phone numbers so that there’s a clear, separate opt-in button for SMS.
• Set up your SMS compliance basics to build trust with your customers and maintain confidence from a legal standpoint:
  • Create a mobile terms of service (TOS) to link anywhere you collect SMS consent.
  • Update your privacy policy to include a description of your SMS marketing program, how you store phone numbers and location data, and the types of messages you’ll send via SMS.
  • Create SMS disclosure language, which must be included anywhere you collect SMS consent. On sign-up forms, it’s best practice to place disclosure language above the submit button, so subscribers understand what they’re opting in to before they sign up.
• While there are multiple SMS opt-in methods in forms, Smart Opt-in is the optimized method for list growth and streamlining the SMS subscription experience.

SMS opt-in methods

Klaviyo provides a number of different ways to collect SMS consent:

• Sign-up forms, with options to collect phone numbers via:
  • Smart Opt-in
  • Tap-to-text
  • Phone number input field
• SMS subscribe links
• Subscribe keywords
• Consent at checkout, available for:
  • Shopify
  • Magento 2
  • BigCommerce
  • WooCommerce
  • PrestaShop
• API

Forms

There are 3 ways to collect phone numbers from your site visitors within a sign-up form:

1. Smart Opt-in (best practice for list growth)
2. Tap-to-text
3. Phone number input field

Smart Opt-in

How it works:

1. Site visitors enter their phone number and submit your sign-up form to receive a message containing a one-time code.
2. The sign-up form shows another step asking for the one-time code.
3. On iOS and Android browsers, visitors can tap to autofill the code. On desktop, they enter the code from their SMS messages. They then submit the code step to confirm their subscription and join your list.

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Benefits:

• Optimizes list growth
  • Smart Opt-in is best practice for increasing list growth because it keeps shoppers on your site during the opt-in process, reducing friction and leading to higher opt-in rates.
• Seamless opt-in experience for your shoppers
  • On mobile, visitors can tap to autofill the code without leaving your site or sending a reply from their messaging app. Desktop visitors enter the code from their SMS messages.
• Accessible for all devices and sending numbers
  • Smart Opt-in works on desktop and mobile devices and with all sending number types (e.g., long code, short code, and branded sender ID). Only display the form in countries where you have an active sending number.
• Utilizes 2-step consent process, similar to double opt-in
  • Collecting SMS consent via Smart Opt-in is similar to the double opt-in process in that visitors take 2 steps to opt in: entering their phone number, and then inputting the one-time code that they receive. Double opt-in is strongly recommended when collecting SMS consent, and in the US it is required if you plan to add SMS to your abandoned cart flows.

Tap-to-text

How it works:

1. Site visitors on mobile and desktop devices see a different option:
   1. On desktop: users enter their phone number and submit the form. If your list uses double opt-in, they must also confirm by text before subscribing.
   2. On mobile:
      • Users click on a button in a form.
      • The user’s messaging app opens with a pre-populated message that contains a subscribe keyword.
      • The user sends the message.
2. On mobile, the next step depends on whether the keyword in your subscribe message uses single or double opt-in:
   • Single opt-in: the user becomes a subscriber immediately.
   • Double opt-in: the user must confirm their subscription before they fully become an SMS subscriber.

Benefits:

• Simple process
  • On mobile, users tap a button and send a pre-populated message, making the opt-in process quick and easy. Keywords set to double opt-in also require confirmation.
• Reduces user errors
  • Eliminates the need for users to manually enter their phone number or other details on mobile, which minimizes the risk of typos or incorrect numbers.
• Utilizes 2-step opt-in process
  • On mobile, users take 2 actions: tapping a button and sending a text. Sending the text verifies that they control the phone number, making this method similar to double opt-in. If the keyword uses double opt-in, they must also confirm their subscription.
• Mobile optimization
  • Tap-to-text is an efficient opt-in method for shoppers on mobile devices, as it leverages the native functionality of mobile phones. You can use dynamic blocks to create distinct views in 1 form so that mobile shoppers see a tap-to-text experience and desktop shoppers see a phone number input field.

Phone number input field

How it works:

1. Site visitors can click the input field in your sign-up form.
2. Users manually enter their phone number.
3. They click the button to submit the form and request an SMS subscription.

For sending numbers that can receive replies, a list set to double opt-in also requires visitors to confirm by text before they subscribe. Branded sender IDs cannot receive replies and use single opt-in with this method.

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Benefits:

• Easy setup
  • Drag a phone number input field into your form from the Add blocks tab. Check that the field collects promotional SMS consent and that the form includes disclosure language. The Phone number only setting stores a number without collecting consent.
• Familiar process
  • A phone number input field in a sign-up form collects phone numbers in a simple, familiar manner that works on all device types.

The phone number field is standard, but is not as mobile-friendly or streamlined as either Smart Opt-in or tap-to-text. In general, display this field only on desktop devices.

SMS subscribe links

How it works:

1. You create an SMS subscribe link and design a subscribe page.
2. Share that link in emails or social media stories, and include SMS disclosure language wherever you post it.
3. Clicking on the link automatically redirects:
   • Mobile users to a tap-to-text experience
   • Desktop users to a subscribe page with a phone input field

Benefits:

• Facilitates SMS list growth
  • SMS subscribe links are dynamic in launching the optimal SMS opt-in experience per shopper’s device, which reduces friction and allows shoppers to quickly sign up.
• Cross-platform accessibility and scale
  • The ability to share an SMS subscribe link in a social media post or story allows viewers to subscribe from any platform, broadening your reach.

Keep in mind that subscribe links only work for 1 sending number. For instance, if you use a toll-free number for both the US and Canada, you can use a single subscribe link to collect SMS subscribers in both countries. However, say you use a short code in Canada. In that case, you need to create a separate subscribe link for each country. You then need to display one link only to the US and the other only to Canada.

Subscribe keywords

How it works:

1. Create custom subscribe keywords (e.g., “JOIN,” “TEXT,” or “SUBSCRIBE”) in your Klaviyo account. Choose the list subscribers will join, select single or double opt-in, and save the keyword.
2. Promote the keyword and your sending number on your website, in emails, or on social media. Include SMS disclosure language wherever you display the keyword.
3. People text that keyword to your sending number to opt in to SMS marketing.
4. Upon texting the keyword, what happens depends on whether the keyword uses single or double opt-in:
   • Single opt-in: the person becomes an SMS subscriber without sending a separate confirmation. A welcome message or offer depends on the messages you configure.
   • Double opt-in: the user must confirm their subscription before they fully become an SMS subscriber.

Benefits:

• Ease of use
  • Subscribing via a simple keyword is quick and easy for customers, reducing barriers to opt-in.
• Subscribe by text
  • Customers can subscribe by texting a keyword without navigating through a form or page. If the keyword uses double opt-in, they must also confirm their subscription.
• Versatile usage
  • Keywords can be used in various contexts (e.g., during events, sales, at point of sale, etc.) and can be promoted in multiple locations to capture a wide audience.

Note that if you have flows that reply to inbound SMS messages, the flow can respond to any word (including, but not limited to, subscribe keywords).

Collect SMS at checkout

How it works:

• If you use Shopify, Magento 2, BigCommerce, WooCommerce, or PrestaShop, you can ask for SMS consent at checkout to target shoppers that are highly engaged with your brand.
• Customers filling out their personal information during checkout can also check a box if they’re interested in opting in to SMS marketing.
• When consent syncs depends on your ecommerce integration. For example, Shopify can sync consent after the customer continues to shipping, without requiring a completed order. For sending numbers that can receive replies, customers must also confirm by text if your list uses double opt-in.

Benefits:

• Streamlined user experience
  • By requesting consent when the customer is already providing information, this approach seamlessly integrates into the user experience, minimizing friction and increasing the likelihood of obtaining consent.
• Target an engaged and interested audience
  • Obtaining consent at the checkout stage ensures you are targeting individuals who have a genuine interest in your offerings, resulting in higher-quality leads for future marketing efforts.

API

How it works:

• You can import SMS consent into Klaviyo from a third-party application or via API.

Benefits:

• You can import SMS consent from any platform you can build on with this method.

Inspiration for using these opt-in methods

Including a subscribe link or a link to a sign-up form in an email

Send an email that includes a subscribe link or a link to one of your sign-up forms to encourage existing email subscribers to opt in to SMS marketing. Email subscribers already have an established relationship with your brand, so they are more likely to trust you and feel comfortable sharing their phone number for SMS communication.

Using a subscribe link or sign-up form link in an email:

• Share an SMS subscribe link in an email
  You can create an SMS subscribe link to share in your emails so that anyone who clicks on it can easily opt in to SMS marketing.
• Link to a sign-up form in an email
  You can embed an SMS sign-up form in a landing page on your website, then send a message (e.g., a flow or campaign) to your existing email subscribers, directing them to the landing page where they can opt in to SMS marketing.

Targeting your Instagram audience

Share an SMS subscribe link in an Instagram story to encourage immediate action from viewers who are already engaged with your content. Instagram stories can have high visibility, so sharing an SMS subscribe link in a story can help you reach a larger audience quickly.

Using a subscribe link in an Instagram story:

• Create an SMS subscribe link to share in your social media channels, such as Instagram, so that anyone who clicks on it can easily opt in to SMS marketing.
  • SMS subscribe links are dynamic in that they automatically optimize the sign up experience for shoppers across all devices, redirecting mobile shoppers to a tap-to-text experience, and sending desktop shoppers to the Klaviyo list’s subscribe page.

Turn an SMS subscribe link into a QR code

You can turn an SMS subscribe link into a QR code, making it easy for customers to share their contact information without slowing down checkout. By placing a QR code in your brick-and-mortar store or on promotional materials, shoppers can quickly scan it to sign up. Directing visitors to a subscribe page through a QR code helps you grow your SMS subscriber list so you can send personalized messages and offers that encourage repeat purchases.

To create a QR code for your subscribe link:

1. In Klaviyo, navigate to Audience > Growth tools.
2. If you have a link, scroll to Manage subscribe links and click Manage. If you do not have a link yet, click Create under Create your first subscribe link, then set up and save a link before continuing. For compliance best practices, the subscribe page tied to your link should collect SMS consent separately from email consent.
3. Next to the subscribe link you want to use, click Copy.
4. Use a third-party tool (e.g., Swapt) to generate a QR code, pasting the copied SMS subscribe link as the destination URL.
5. Generate the QR code and add it to posters, business cards, flyers, and more. Include SMS disclosure language beside the QR code so shoppers know what they are signing up for.

Showing a keyword on your website

Use a subscribe keyword alongside a contest, survey, or quiz to invite website visitors to your SMS program. Include disclosure language wherever you display the keyword, and explain both the activity and the messages subscribers will receive.

Using a subscribe keyword to invite visitors to a quiz:

1. Use a third-party tool to create a quiz.
2. Create a custom subscribe keyword and choose the list subscribers will join. Promote it on your website with your sending number and SMS disclosure language (e.g., “Text FLAVOR to [your sending number] to subscribe to SMS updates and get a link to our next cookie flavor quiz”).
3. After visitors subscribe and complete any required double-opt-in confirmation, send them an SMS message with a link to the quiz. They can then complete the quiz in your third-party tool.

When using custom keywords, it is imperative to clearly explain the purpose of the sign up (via disclosure language) and strictly adhere to that purpose. For example, if consent is obtained for a one-time quiz, you are not permitted to send additional SMS messages beyond that scope. However, you can try targeting this group to encourage opt-in for general marketing messages separately.

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