Key Takeaways:
Most businesses approach GDPR compliance for SMS marketing with a mix of confusion and dread. The regulations seem intentionally complex, the penalties feel disproportionate, and the practical guidance available online ranges from overly technical legal analysis to dangerously oversimplified checklists that miss critical requirements.
The reality is that GDPR compliance for SMS marketing isn't actually complicated once you understand what the regulation actually requires versus what lawyers worry about in worst-case scenarios. You need explicit consent properly documented, transparent data practices, respect for individual rights, and security measures protecting customer information. These aren't unreasonable demands. They're basic respect for the people you're marketing to.
This guide walks through exactly what GDPR requires for SMS marketing and how to implement each requirement practically. You'll learn how to build compliant consent processes, maintain proper documentation, handle individual rights requests, and structure your SMS marketing program to satisfy GDPR without killing your ability to actually market effectively.
The General Data Protection Regulation applies to any business marketing via SMS to people located in the European Union or European Economic Area, regardless of where your business is located. If you're texting customers in France, Germany, Spain, or any other EU/EEA country, GDPR governs how you collect consent, store data, and communicate.
At its core, GDPR establishes rules for processing personal data. Phone numbers are personal data. SMS marketing is processing. Therefore, you need a legal basis to send marketing texts to EU/EEA recipients.
For SMS marketing, that legal basis is almost always consent. The regulation technically allows other legal bases like "legitimate interest," but marketing texts rarely satisfy the balancing test required. Direct marketing via electronic communications demands explicit consent in practice.
GDPR operates on six fundamental principles that inform every compliance requirement:
Lawfulness, fairness, and transparency: You must have legal basis for processing (consent), treat people fairly, and be transparent about what you're doing with their data.
Purpose limitation: You can only use data for the specific purposes you told people about when collecting it. If someone consented to appointment reminders, you can't suddenly start sending promotional offers without getting separate consent.
Data minimization: Collect only the data you actually need. For SMS marketing, that's typically phone number, name, and consent records. You don't need birthdate, address, or other information unless specifically relevant to your marketing.
Accuracy: Keep data current and correct inaccurate information when discovered or when people request corrections.
Storage limitation: Don't keep data longer than necessary for the purposes you collected it. Define retention periods and actually delete data when those periods expire.
Integrity and confidentiality: Implement appropriate security measures to protect personal data from unauthorized access, loss, or damage.
These principles aren't just theoretical. They translate directly into practical requirements for how you build and operate SMS marketing programs.
Consent under GDPR must be "freely given, specific, informed, and unambiguous." Each word in that phrase has specific meaning that affects how you collect opt-ins.
Freely given means people have real choice without negative consequences for refusing. You can't make SMS opt-in a condition of service unless the texts are genuinely necessary for that service. Promotional marketing texts are never necessary in this sense.
Specific means consent for one purpose doesn't cover others. Email consent doesn't cover SMS. Appointment reminder consent doesn't cover promotional offers. Each use requires separate, explicit consent.
Informed means people understand what they're consenting to. Your consent request must clearly explain who you are, what you'll send, how often, and how they can withdraw consent.
Unambiguous means consent requires clear affirmative action. Silence, pre-ticked boxes, or inactivity don't constitute consent. People must actively opt in through actions like checking an unchecked box or clicking a confirmation link.
Your SMS opt-in process needs several specific elements to satisfy GDPR:
Clear identification: State your business name and that you're requesting consent for SMS marketing. Don't hide this in general terms and conditions or privacy policies.
Explicit scope: Specify what types of messages people will receive. "Promotional offers and updates" is acceptable. "Communications from us" is too vague.
Frequency indication: Give people a sense of how often you'll text. "Weekly updates" or "occasional promotions" sets appropriate expectations.
Opt-out information: Explain how people can withdraw consent. "Reply STOP to opt out at any time" is standard and acceptable.
Separate action: SMS consent must be a distinct action from other consents. Don't bundle it with email, terms acceptance, or account creation unless each has its own checkbox.
Affirmative opt-in: Use unchecked boxes that people must actively check. Never use pre-checked boxes or assume consent.
Here's what this looks like in practice:
❌ Non-compliant: "By creating an account, you agree to receive communications from us."
✅ Compliant: I consent to receive promotional SMS messages from [Business Name] with offers and updates (approximately 2-4 messages per month). I can opt out anytime by replying STOP. Standard message and data rates apply.
The compliant version identifies the business, specifies SMS specifically, explains message types and frequency, provides opt-out information, and requires affirmative action.
Double opt-in sends a confirmation message after initial opt-in, requiring people to confirm their subscription before you add them to your marketing list. While not always legally required under GDPR, it provides several advantages:
It proves the person who entered the phone number actually owns it and intended to subscribe. This protects against malicious opt-ins where someone subscribes another person's number without permission.
It creates documented proof of consent with timestamp and confirmation action. This evidence helps if consent is ever questioned.
It reduces complaints and improves list quality by ensuring only genuinely interested people join your SMS list.
For high-risk marketing or valuable customer relationships, implement double opt-in even when not strictly required. The added protection justifies the minor friction in the subscription process.
GDPR imposes strict rules on what data you collect, how you store it, and how long you keep it. For SMS marketing, you need to think carefully about each piece of information you're gathering.
Collect only data actually necessary for your SMS marketing purposes. Essential data typically includes:
Data you likely don't need for basic SMS marketing:
Before adding fields to opt-in forms, ask whether that data is genuinely necessary for the SMS marketing you're conducting. If you can't articulate why you need it, don't collect it.
GDPR requires "appropriate technical and organizational measures" to protect personal data. For SMS marketing data, this means:
Encryption: Store phone numbers and personal data encrypted at rest and in transit. Your SMS platform should handle this, but verify their security measures.
Access controls: Limit who can access customer data. Not everyone on your team needs access to your entire contact list. Implement role-based permissions.
Audit logs: Track who accesses data and when. If a breach occurs or someone questions how their data was used, audit logs provide answers.
Regular backups: Protect against data loss while ensuring backed-up data receives the same security as primary data.
Vendor security: Your SMS platform stores customer data. Verify they implement appropriate security measures through their documentation and DPA.
Most of this happens through your SMS platform's security infrastructure. Sakari's platform implements enterprise-grade security including encryption, access controls, and audit logging to help businesses satisfy GDPR security requirements.
You can't keep data indefinitely. GDPR requires deleting data when it's no longer necessary for the purposes you collected it.
Define clear retention periods:
Active subscribers: Keep data as long as they remain opted in and engaged.
Inactive subscribers: Consider removing contacts who haven't engaged in 18-24 months after re-engagement attempts fail.
Unsubscribed contacts: The retention question for opt-outs is nuanced. You need to keep some record that someone unsubscribed to avoid re-adding them accidentally. But you don't need to keep their full contact record. Many businesses retain just the phone number and opt-out status, deleting other personal data.
Consent records: Keep consent documentation for 3-5 years even after someone unsubscribes. This proves compliance if questions arise later.
Implement automated deletion where possible. Manual data deletion gets forgotten. Automated processes ensure retention policies actually execute.
GDPR grants individuals specific rights regarding their personal data. Your SMS marketing program must accommodate these rights within defined timeframes.
People can request information about what personal data you hold about them and how you're using it. For SMS marketing, this means providing:
You have 30 days to respond to access requests. Build a process for handling these requests before you receive them.
Create a standard response template that pulls together the relevant information. If someone requests their data, you need to compile it quickly without scrambling.
If someone's data is inaccurate, they can request corrections. For SMS marketing, this typically means updating phone numbers or names.
This should be straightforward. When someone says "you have the wrong number for me," update it. Document the change and confirm with the person.
The 30-day response deadline applies here too, though most corrections happen much faster in practice.
People can request deletion of their personal data in certain circumstances. For SMS marketing, the most common scenario is simply wanting out of your marketing completely.
When someone requests deletion:
You have 30 days to complete deletion requests, but act faster when possible. People requesting deletion are often frustrated. Quick action reduces complaints and demonstrates respect for their rights.
People can object to processing at any time. For SMS marketing, this essentially means opting out.
Treat objections the same as deletion requests. Stop marketing immediately and remove them from your lists. The right to object isn't limited to formal requests. A simple "stop texting me" counts as objection and must be honored immediately.
People can request their personal data in a structured, commonly used format to transfer to another service. For SMS marketing, this rarely comes up because there's limited reason to port SMS subscription data.
If requested, provide the data in CSV or JSON format containing the person's contact information and interaction history.
GDPR requires that withdrawing consent must be as easy as giving it. If someone can opt in with a single checkbox, they must be able to opt out just as easily.
For SMS marketing, this means implementing multiple opt-out methods:
Reply-based opt-out: Allow people to opt out by replying STOP, UNSUBSCRIBE, or similar keywords to any message. This is the minimum acceptable standard.
Link-based opt-out: Include unsubscribe links in messages where appropriate. For longer messages with URLs, provide a direct opt-out link.
Account-based opt-out: If you have customer accounts or portals, include SMS preference management where people can opt out or adjust frequency.
Support-based opt-out: Accept opt-out requests via any channel people contact you through - email, phone, chat, social media. Don't force people to use a specific method.
Process all opt-outs immediately. "We'll remove you within 10 business days" doesn't satisfy GDPR. The next scheduled campaign might be acceptable, but days of delay is not.
Sakari's platform automatically handles keyword-based opt-outs, removing contacts immediately when they reply STOP and preventing further messages to opted-out numbers.
When someone opts out, you face a data retention paradox. GDPR says delete data when it's no longer needed. But if you delete everything, you might accidentally re-add someone who opted out.
The solution is keeping minimal opt-out records:
Delete everything else:
This minimal record prevents re-subscription while respecting the person's desire to be forgotten. You're not marketing to them or using their data for any purpose beyond honoring their opt-out preference.
GDPR requires proving compliance, not just achieving it. Without proper documentation, you can't demonstrate that you obtained consent properly, honored individual rights, or followed your stated data practices.
For every person on your SMS marketing list, maintain records showing:
Who consented: The specific phone number and associated contact information
When they consented: Exact timestamp of opt-in action
Where they consented: The specific form, webpage, or interaction where opt-in occurred
What they consented to: The exact consent language they agreed to
How they consented: The mechanism (checkbox, confirmation text, etc.)
Proof of consent: Log entries, form submissions, or other evidence the action occurred
This documentation proves compliance if someone claims they never opted in or if regulators audit your consent practices.
Many businesses fail at consent documentation. They have lists of phone numbers but can't prove how or when those people consented. This puts them at serious risk.
Implement automated consent logging that captures all required information without requiring manual record-keeping. Your SMS platform should handle this, but verify the logging actually works.
GDPR requires informing people about your data practices through privacy notices. For SMS marketing, your privacy policy must explain:
Make your privacy policy accessible from opt-in forms and include a brief privacy notice at point of consent:
"We'll use your phone number to send promotional texts. See our Privacy Policy for details: [link]"
This satisfies the "informed consent" requirement by ensuring people can access full information about data practices before opting in.
Build documentation systems that automatically track compliance-related actions:
If regulators question your practices or someone files a complaint, these records prove compliance. Without them, you're arguing from memory against documented accusations.
Most compliance violations that result in penalties involve not just bad practices but inability to prove good practices. Documentation protects you.
Your SMS platform processes personal data on your behalf. Under GDPR, this makes them a data processor and you the data controller. This relationship requires a formal Data Processing Agreement (DPA).
A compliant DPA specifies:
Scope of processing: What data the processor handles and for what purposes (sending SMS messages, storing contact data, etc.)
Security measures: What technical and organizational measures the processor implements to protect data
Sub-processors: Whether the processor uses other parties and how they're managed
Data subject rights: How the processor assists you in responding to individual rights requests
Breach notification: How quickly the processor notifies you of data breaches
Data location: Where data is stored and processed geographically
Audit rights: Your ability to verify the processor's compliance
Data deletion: What happens to data when you stop using the service
Liability: Who's responsible if something goes wrong
Most reputable SMS platforms provide standard DPAs that satisfy GDPR requirements. Review these agreements to understand your responsibilities and the platform's commitments.
Sakari provides compliant DPAs covering all required elements for GDPR compliance. The platform's security measures, data handling practices, and contractual commitments support your compliance obligations as data controller.
Before selecting an SMS platform, verify they can support your GDPR compliance:
Don't assume platforms automatically comply with GDPR. Ask specific questions and review their documentation before committing.
GDPR compliance isn't something you add after building your SMS marketing program. It must be embedded from the beginning through privacy by design principles.
Start with proper consent collection:
Test your opt-in process thoroughly. Submit test opt-ins and verify all information logs correctly. Check that consent timestamps, sources, and language are captured.
Build compliance into your campaign workflows:
Consent verification: Before adding anyone to a campaign, verify they have active consent for that specific message type. Don't send promotional offers to people who only consented to appointment reminders.
Automatic opt-out processing: Configure your platform to immediately remove people who reply with opt-out keywords. No manual intervention should be required.
Retention enforcement: Set up automated deletion for contacts who've been inactive beyond your retention period.
Documentation generation: Ensure every campaign logs what was sent, when, and to whom for compliance records.
Sakari's workflow automation includes built-in compliance features like automatic opt-out handling and consent-based segmentation to help businesses maintain GDPR compliance at scale.
Schedule quarterly reviews of your SMS marketing compliance:
Treat compliance as ongoing practice, not one-time setup. Regulations evolve, your marketing practices change, and team members need regular reminders of proper procedures.
Understanding penalties helps calibrate your compliance investment. GDPR allows fines up to €20 million or 4% of global annual revenue, whichever is higher. These maximum penalties grab headlines but rarely apply to typical SMS marketing violations.
Actual enforcement follows a tiered approach based on violation severity:
Minor violations: Missing documentation, unclear privacy notices, small consent issues typically result in warnings and orders to fix problems within specific timeframes. Fines are uncommon for first-time minor violations when businesses cooperate.
Moderate violations: Systematic consent problems, poor security, delayed responses to rights requests can result in fines ranging from tens of thousands to hundreds of thousands of euros depending on company size and violation scope.
Serious violations: Ignoring individual rights, marketing without any consent, major data breaches due to negligence result in substantial fines potentially reaching millions of euros.
Regulators consider several factors when determining penalties:
The lesson: implement genuine compliance efforts, document your practices, and respond quickly when issues arise. Regulators distinguish between businesses trying to comply and those ignoring obligations entirely.
GDPR compliance for SMS marketing comes down to respecting people's data and being transparent about your practices. Obtain proper consent. Document what you're doing. Honor individual rights. Implement reasonable security. Delete data when you no longer need it.
These aren't burdensome requirements. They're reasonable expectations for businesses handling customer information. The complexity comes from legal language and enforcement uncertainty, not from the underlying principles.
Start with the foundation: fix your consent process if it's not compliant. Everything else builds from there. You can't have compliant SMS marketing without proper consent, but with proper consent, most other requirements become manageable.
Use technology to automate compliance where possible. Your SMS platform should handle opt-out processing, consent logging, and data security without requiring constant manual intervention. This lets you focus on creating effective marketing rather than managing compliance minutiae.
Ready to implement GDPR-compliant SMS marketing without the legal headaches? Start your free trial with Sakari and access built-in compliance features including automated consent management, opt-out processing, and documentation tools that help you satisfy GDPR requirements while building effective customer relationships.