Understanding SMS consent collection

You will learn

Learn about SMS consent, including what counts as SMS consent, how you can collect it, and how resubscribes work. SMS consent refers to whether someone is opted in (i.e., if they have agreed to receive marketing text messages from your brand). 

For information on how to tell if a profile is consented to SMS, see this article on how Klaviyo stores consent. 

Before you begin

In Klaviyo, you must have 2 things before you can collect SMS consent:

• SMS turned on.
• An active sending number in the country where you want to collect SMS consent. The number may also need to be verified or registered.

If you haven't enabled SMS, or don't have a sending number for that country, you cannot collect SMS consent. 

What counts as SMS consent

SMS is more regulated than most other marketing channels. Due to this, there are stricter requirements on what counts as proper SMS consent. Below, we break down what you need to do for SMS. 

Individuals must explicitly agree to receive SMS messages

Someone must agree to receive SMS messages from your brand, regardless of whether you're sending marketing or transactional messages. Typically, someone subscribes by checking a box at checkout or signing up through a form. 

SMS consent also must be collected separately from any other marketing channel. For instance, while you can collect both email and SMS consent in the same form, you must make it clear that SMS is optional (usually via a separate checkbox or button).  

A single consent cannot be provided to multiple brands or organizations. Customers must provide consent to receive messages from your company explicitly. Lead generation, affiliate related, or purchased lists are not valid SMS consent.

You cannot force SMS consent

It’s illegal to force someone to sign up for SMS in order to make a purchase. 

Additionally, providing consent for SMS cannot appear as if it’s required. Even if giving SMS consent is optional for your customers, you may face fines or compliance issues if SMS consent seems required. For instance, collecting both SMS and email consent on the same step of a sign-up form is not recommended, as customers may think they have to sign up for SMS if they want to sign up for email. 

Use disclosure language wherever you collect SMS consent

SMS subscribers must understand what they’re agreeing to before they sign up. To make this clear, include disclosure language wherever you collect SMS consent, whether that is on a checkout page, form, banner in an email, social media post, or a third-party quiz or form (when using APIs to send consent). 

This goes for all opt-in methods, from sign-up forms to subscribe keywords. Any potential subscriber should understand what they're signing up before they click submit or text in a keyword.  

Use double opt-in if using cart abandonment messages (US)

While double opt-in is always recommended, it's also a carrier requirement in the US for any shopping cart abandonment flow (e.g., abandoned cart, added to cart, etc.). 

With double opt-in, someone must take 2 actions before they're added as a subscriber in your account, such as entering their phone number and then confirming via text or clicking a button and then texting a keyword. 

FAQs

How to collect consent

There are several different ways you can collect SMS consent. 

A few of these options should be done when you first start with SMS, while others can be left for later or only in certain scenarios. Because of this, we’ll break them down into 3 categories: 

1. Basic (what everyone should do as soon as they start with SMS)
2. Intermediate (what you can leave for later)
3. Advanced (what only select users should do)

We'll briefly cover the different methods for collecting SMS consent in this article and link to other, more detailed articles for step-by-step instructions for when you're ready to build your consent channels!

Basic methods

These are actions everyone should take when they first set up SMS. There 2 basic forms of collecting SMS consent:

1. Create sign-up forms that target new subscribers and your current email subscribers (estimated time: 10–15 minutes).
   • Generally, the most efficient type of form is Smart Opt-in; however, this isn't available for forms that collect SMS transactional consent. 
2. Collect SMS consent at checkout for your ecommerce store: (estimated time: 10 minutes).
   • Shopify
   • WooCommerce
   • BigCommerce
   • Magento 2
   • PrestaShop

Intermediate methods

These consent methods don’t need to be done as soon as you set up SMS. Instead, wait until you have finished setting up the basic consent collection steps, key SMS flows, such as your SMS welcome, abandoned cart, and post-purchase flows; and the rest of the steps recommended in our Getting started with SMS course.

1. Use emails to collect SMS consent (estimated time: 10 minutes).
2. Create a subscribe link for sharing in ads or on social media (estimated time: 5–10 minutes).
   • Collect SMS consent via Instagram stickers (estimated time: 5 minutes).
     Note that these steps are only for businesses who are already using Instagram.

Advanced methods

Advanced consent collection methods require a developer or someone experienced with making API calls. By making API calls, you can transfer SMS consent into Klaviyo from a third-party sign-up form or information from a quiz.

For details, see our Developer Portal article on collecting email and SMS consent via API.

With some third parties (including Privy and Justuno), you don’t need to set up the API call yourself, as they will sync SMS consent to Klaviyo via an integration.

Note that you still need proper disclosure language wherever you collect consent, including if you’re using the API. 

Resubscribing to SMS

Depending on how someone opted out, they may need to resubscribe in a certain way. Note that for the UNSTOP and START keywords, you must have an "SMS Subscribers" list, titled and capitalized exactly as shown. 

If you have a toll-free number and someone previously texted STOP, the only way for them to be resubscribed is for them to text the words START or UNSTOP. This is required by wireless carriers in order for them to deliver messages. If they use some other method to resubscribe, the profile will show the individual as opted in, but wireless carriers will not deliver any messages to that recipient until they text the word START or UNSTOP.

If your customer did not opt out via the STOP keyword, and instead used an unsubscribe link, they can resubscribe using forms, START or UNSTOP, or via checkout. Similarly, if you have a short code, your customers can resubscribe by any method. 

Additional resources

• Want more information on SMS? Check out:
  
  • Basics of SMS compliance
  • Create popups to collect SMS consent
• Understanding consent in profiles
• See tips on mobile form design