Understanding SMS Consent Collection

Understanding SMS Consent Collection

Getting SMS marketing right starts with one crucial principle: permission. SMS consent collection is the legal and strategic foundation for responsible mobile messaging. Without it, your marketing efforts risk violating customer trust and data protection laws like the GDPR.

Whether you are promoting offers or sending reminders, consent is what separates welcome communication from unwanted spam. At LINK Mobility, we help businesses collect, manage, and act on SMS consent in full compliance with GDPR and other regional regulations.

SMS marketing remains one of the most effective direct channels, with open rates as high as 98%. But before you send a single message, you must have the right level of consent based on the message type.

There is no one-size-fits-all rule for SMS consent. The permission level required depends on the content, who initiates the conversation, and how the customer’s data was collected.

Here’s a breakdown of the different types of SMS content and what level of consent is required:

Type of SMSInitiatorContent ExampleRequired Consent
PromotionalBusinessSales, offers, discount codes, CTAsExplicit consent
TransactionalBusiness or CustomerOrder confirmation, appointment reminderExplicit consent
Inbound ConversationalCustomerCustomer requests information and receives a responseImplicit consent
Outbound ConversationalBusinessBusiness initiates conversation with push messageExplicit consent
NotificationsBusinessService alerts, delivery updates, policy changesExplicit consent
OTP (One-Time Password)CustomerLogin verification code, payment authenticationImplied consent

Understanding these distinctions is essential not only for building trust but also for staying compliant with data privacy laws. The wrong type of message, sent without the right consent, can lead to customer complaints or, worse, legal penalties.

Let us take a closer look at each category and what it means in practice:

  • Promotional messages always require opt-in written consent.

  • Transactional messages require clear consent for that specific interaction.

  • Conversational replies, when initiated by the customer, require no prior opt-in but must stay relevant to their inquiry.

This is not just good practice; it is required under regulations like the GDPR, which emphasizes customer control, data purpose limitation, and secure data handling.

The General Data Protection Regulation (GDPR) applies to any business handling the personal data of EU citizens. It requires:

  • Explicit and informed consent for promotional messages.

  • Transparent communication about how data will be used.

  • Proof of consent (stored in a compliant format).

  • Easy opt-out options for all recipients.

LINK Mobility supports businesses in meeting these GDPR requirements by providing a fully compliant messaging infrastructure. Our tools make it simple to store and manage consent, verify opt-in records, and automate unsubscribe flows, without adding complexity to your campaigns.

There are many ways to gather SMS opt-ins, through website forms, QR codes, in-store campaigns, app onboarding, and more. But no matter how you collect consent, three foundational principles must be in place to ensure your SMS marketing is legally compliant and ethically sound.

  1. Voluntary
    The customer must actively choose to receive SMS messages. This means no pre-ticked boxes or bundled consent hidden in terms and conditions. Opt-in should be a clear, separate action taken without pressure.

  2. Informed
    People need to understand exactly what they are signing up for. That includes what kind of messages they will receive (e.g., promotions, order updates), how often they will hear from you, and how they can opt out.

  3. Documented
    You must be able to prove that consent was given. Whether someone opted in via a form, chat, or SMS keyword, keeping a record of the time, method, and context of that consent is key to staying compliant, especially under regulations like GDPR.

By following these principles, your business not only protects itself legally but also builds stronger, more trusted customer relationships.

Collecting SMS consent does not have to feel like a legal formality, it can be an integrated part of how you engage customers across digital and offline touchpoints. What matters is that consent is clear, actively given, and easy to manage.

Let’s look at a few different formats businesses use to gain compliant SMS opt-ins in practice:

  • Promotional Landing Pages
    E-commerce brands often create seasonal landing pages where users can sign up to get early access to limited-time sales. These pages include a simple SMS field and a clear description of what messages will follow, usually limited to sales alerts and exclusive coupons.

  • Loyalty Program Sign-Ups
    Retailers collecting loyalty sign-ups online or in-store include mobile number fields with a consent box for SMS updates. Because loyalty programs already focus on exclusivity and perks, SMS adds value and feels like a natural part of the membership.

  • Event Registrations and Ticketing
    In industries like entertainment or hospitality, SMS consent is gathered when users register for events. The opt-in comes with the promise of reminders, changes to the schedule, or last-minute offers, making it both relevant and welcomed.

  • Customer Surveys and Feedback Requests
    After purchases, businesses sometimes offer a discount in exchange for feedback. At the end of the survey, customers can choose to opt in to receive future offers via SMS, an effective way to follow up with already engaged users.

  • Post-Purchase Transactional Flows
    In cases where customers receive a shipping or appointment confirmation by email, brands often prompt them to add their phone number for future SMS updates. This opt-in feels helpful, not promotional, opening the door for transactional messaging with consent clearly logged.

With LINK Mobility, you can implement and automate all of these use cases across your tech stack, ensuring that opt-ins are securely stored, legally compliant (including GDPR), and tied to clear message types. You also gain tools for customer preference management, allowing people to fine-tune what kind of SMS they want to receive.

Getting consent right can be complex. That is why businesses across Europe choose LINK Mobility, not just for our messaging infrastructure, but for the built-in compliance and expert support.

We help you:

  • Collect and store consent securely and transparently

  • Segment audiences based on consent type and customer behavior

  • Automate opt-in and opt-out flows in your campaigns

  • Stay compliant with GDPR, local telecom regulations, and best practices

  • Send SMS at scale with the right permissions in place

No matter your industry - retail, finance, logistics, healthcare, or public services, our tools ensure your SMS campaigns are both effective and responsible.

SMS consent collection is not just a legal box to tick, it is a critical part of building trusted relationships and long-term customer engagement. With the right processes and technology in place, you can grow your SMS list ethically, stay compliant, and deliver messages your customers actually want. LINK Mobility provides the infrastructure, compliance expertise, and tools you need to make it happen. Contact us today to see how we can help you build a permission-based SMS strategy that supports growth while staying within the lines.

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If you would like to explore the subject further, discuss ideas, or understand how it could apply to your business, we are here to continue the conversation.

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