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Play by the rules: What you need to know about SMS opt-in and opt-out requirements.

Last updated October 2023

To send text messages to your customers, it’s important to understand and follow the rules around SMS compliance. If you don’t, hefty fines and penalties could come your way – not to mention costly damage to your reputation.

The good news? SMS compliance isn’t hard. Take five to wrap your head around the SMS opt-in and opt-out rules below, and then make sure you’re following them.

Just so you know, we can’t give legal advice

This blog contains general information. The content of this blog does not constitute legal advice, is not intended to be legal advice, and should not be relied on as such. It’s important to seek your own legal advice about text messaging rules and regulations.
That’s why we recommend you check in with the primary sources that are making the rules, such as the Telephone Consumer Protection Act (TCPA).

First up, follow these guiding principles

According to the CTIA, any business that sends text messages should follow some core rules or guidelines. These guiding principles provide a baseline for all your sending.

  1. Display clear calls-to-action. Make sure it’s crystal clear what will happen as the result of a click or action (e.g. wording to the effect that a customer will be signing up to receive marketing SMS on an ongoing basis). Customers need to know exactly what they are signing up for.
  2. Provide applicable consent mechanisms. Consent is required by law under the TCPA. Express consent applies to certain messages (such as marketing messages), but in some situations implied consent will suffice.
  3. Send opt-in confirmation messages.  It is good practice to confirm a customer’s opt-in in the first message you send to them.  For single-message programs, the confirmation message content may be part of a single message you send after the customer opts in. For recurring-messages programs, confirmation messages must include clear opt-out instructions.
  4. Acknowledge and honor opt-out requests. You must acknowledge and act on all opt-out requests – for example, by sending a message that says, “You will no longer receive text messages from us”. Monitoring procedures should be implemented to confirm successful opt-out.

Get consent before you hit ‘send’

Consent is the golden rule of SMS compliance. You must ask your customers to opt-in to most types of messages – yet the type of consent you need depends on the type of message you’re sending.

Below are the three types of messages and their rules for consent. These rules come from the Telephone Consumer Protection Act of 1991 (TCPA) – if you don’t follow them, you could face between $500 and $1,500 in regulator fines or class action damages for every unsolicited text message you send. Ouch.

1. Opt-in rules for promotional messages

Promotional or marketing messages are all about boosting your sales, promoting your products, or raising brand awareness. These are outbound messages from your business.

Before you send promotional messages to a customer, they need to agree in writing to receive these types of texts. If you already ask customers to sign a form or submit their contact information, it can be as simple as adding a field to opt-in to marketing messages.

Note that adding a call-to-action like a coupon code to an informational message may mean the message is deemed a promotional text, and so the opt-in rules for promotional messages would apply. 

2. Opt-in rules for informational messages

These types of messages contain information. Examples can include appointment reminders, welcome texts, and alerts – and they can be one-way updates or two-way conversations.

To send informational messages to customers, you need consent.

When they give you their phone number, the customer needs to provide express permission for you to send them texts for a specific informational purpose. This permission can be given via text, on a form, on a website, written, or verbally.

Transactional messages contain information that is necessary for your customers to use your product or service and, to date, have seen fewer TCPA violation actions.

3. Opt-in rules for conversational messages

Conversational messaging is a back-and-forth, two-way conversation that takes place via text, and starts with the customer sending you a message. For example, they might text your business with a quick question about the availability of a product, and you respond with a short answer.

When the customer initiates the conversation and you’re simply responding to their text, you don’t need verbal or written permission from the customer.

In other words, conversational messaging which is instigated by a customer requires implied consent only.

Follow the SMS opt-out rules, too

Whenever you send SMS messages, you must provide a way for customers to tell you they no longer wish to receive communication from you.

Messages need to provide clear instructions on how to opt out of future messages, and most companies choose to utilize words such as ‘STOP’ or ‘UNSUBSCRIBE’. So, for example:

  • To opt out of future promotions, please reply STOP
  • Text STOP to unsubscribe
  • To unsubscribe, reply STOP

If you are sending in another language, you need to include the relevant opt-out wording in that language as well.

Our team is here to help.

Still have questions about SMS opt-in and opt-out rules? Sinch MessageMedia can help.

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FAQs about SMS opt-in requirements.

Opt-in SMS means that you can only message customers if they have agreed to it. If you send texts to customers who have not opted in to your messages, you may be in violation of the Telephone Consumer Protection Act (TCPA).

If your customers have opted into your text messages, they have the right to opt out at any time. If they opt out of your SMS campaigns, your business can no longer contact them via SMS.

Before sending messages to your customers via SMS, they need to opt-in to your messages. This is important for remaining compliant with government regulations. Customers also have the ability to opt-out at any time.

To send messages to customers via SMS, businesses need to obtain express consent. For example, this may be in the form of a checkbox on a website for users to opt-in to receiving your SMS messages.