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Get an overview of 7 important aspects of SMS compliance.
This advice is for informational purposes only and is neither intended as nor should be substituted for consultation with appropriate legal counsel and/or your organization’s regulatory compliance team.
The 7 compliance basics for SMS
- Always get consent for SMS before texting anyone
- Make it easy to unsubscribe
- Avoid prohibited content
- Don't send too early or late
- Indicate your company or brand in every SMS
- Follow rules for abandoned cart flows (US only)
- Add other message requirements (Canada only)
Always get consent for SMS before texting anyone
When it comes to SMS, you must have someone's express consent in order to message them. Written consent is best, as there’s a record of someone agreeing to SMS.
To get proper SMS consent, there are 3 key best practices you should keep in mind.
Don't send SMS to anyone who is not a current subscriber. This applies to all message types, including:
- Flows
- 1-on-1 conversations
- Campaigns
Even if someone previously opted into SMS but is now opted out, you cannot text them because they are not currently a subscriber.
When it comes to getting consent, someone must agree to receive SMS messages, so keep the following in mind:
- SMS opt-in must be separate from email
- You can't use the same checkbox for both
- Consent for email or marketing in general doesn't count
SMS also requires that people understand what they're opting into. You must include disclosure language to tell people about your SMS program anywhere you collect SMS consent, including:
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- Popups
- Flyout
- Embed forms
- Printouts with QR codes
- Instagram stickers
- Checkout page
- Emails with opt-in links
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Want an example? Go to this article for an example of disclosure language.
Make it easy to unsubscribe
Always include a way for subscribers to opt out of your SMS campaign and flow messages.
Depending on what sending number you're using, you can include one of the following in your SMS messages:
- Opt-out keyword (e.g., STOP)
- Unsubscribe link
These are the simplest options, although any other reasonable opt-out method may also be allowed (e.g., providing your customer support phone number or email address in the SMS).
| Example of an opt-out keyword | Example of an unsubscribe link |
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Avoid prohibited content
There are certain topics that wireless carriers refuse to deliver to recipients.
Anything related to these prohibited topics in either your messages or website may result in your messages getting filtered by the carrier or the carrier completely blocking the sending number.
- Illegal substances
- SHAFT
- Sex
- Hate
- Alcohol
- Firearms (including fireworks)
- Tobacco (including CBD)
- Gambling
- Debt collection/forgiveness
- High-risk financial services (e.g., cryptocurrency)
- Multi-level marketing
While not all these topics are prohibited in every country, carriers reassess what content they will allow and don't always make this information public in a timely or formal manner. It's best to avoid them no matter which country you're sending to.
Don't send too early or late
There are certain times when it's illegal to send SMS. These hours are known as quiet hours, and they vary based on the country and region you're sending to.
As a best practice, do not send:
- Before 9 a.m.
- After 8 p.m.
Times are determined by the recipient's time zone (not yours, as the sender).
Indicate your company/brand in your SMS
It's important for your subscribers to know who your messages are from. Otherwise, your recipients may think the texts are just spam.
There's a couple different ways you can tell customers who you are in your text messages:
- Include an organization prefix at the beginning of the message
- Reference your brand somewhere in the body of the text message
- Use a branded sender ID (UK or Australia only)
- Send a virtual contact card as part of your welcome series (US and Canada only)
Follow rules for abandoned cart flows (US only)
- Always use double opt-in
- Only send 1 SMS in an abandoned cart flow
- Send the SMS within 48 hours of an individual abandoning a cart
Add other message requirements (Canada only)
Every text sent to Canadian recipients requires the following elements:
- Program name (e.g., for Klaviyo, it might be “Klaviyo SMS”)
- A call to action
- Reply HELP for help
- Reply STOP to opt out
- “Std. Msg&Data rates may apply”
For example, a message about a new product might look like this: “Bridge Designs: Fall season is here! Check out our new pieces here: [LINK] Text HELP for help. Text STOP to opt out. Std. Msg&Data rates may apply.”
Additional resources
- See country-specific laws for SMS
- Find out more about the US law for abandoned carts
- Learn more about quiet hours