SMS + email: the UK compliance-safe combo
SMS + email: the UK compliance-safe combo
How UK DTC brands run SMS alongside email without breaking PECR or GDPR - opt-in, timing, message caps and the flows where SMS actually earns its place.
The legal position
SMS marketing in the UK is governed by PECR (Privacy and Electronic Communications Regulations) and UK GDPR. You need explicit, freely-given, informed opt-in. Pre-ticked boxes, bundled consent, or "opt-in to receive shipping updates and marketing" are non-compliant.
Compliant opt-in patterns
- Dedicated, unticked SMS opt-in at checkout with clear frequency ("2-4 msgs/month").
- Standalone SMS opt-in on a keyword-based landing page.
- Post-purchase opt-in with clear message purpose.
Never assume SMS consent from email consent - they are separate under PECR.
Cadence
3-5 SMS per month maximum. Beyond that opt-outs spike above 2%/month and list value collapses inside a year.
Where SMS earns its place
- Abandoned cart (hour 4) - +4-7% recovery.
- Shipping/delivery updates - service, not marketing.
- Back-in-stock alerts - high intent.
- Time-sensitive campaigns (flash sale, launch day).
Where SMS doesn't belong
- General newsletters.
- Welcome flow (email handles this).
- Birthday.
- Educational or brand-story content.
Copy principles
- 140 characters or less.
- Brand name in first 5 characters.
- One clear CTA + link.
- Always include STOP instructions ("Reply STOP to opt out").
ICO enforcement
The ICO has fined UK brands £130K+ for non-compliant SMS. If you can't evidence opt-in for every number on your list, don't send to it.
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Related tools & resources
Free UK ecommerce calculators, definitions and benchmarks referenced in this guide.
Frequently asked questions
Yes, with explicit opt-in under PECR. A pre-ticked box or bundled consent at checkout is not compliant - use a dedicated, unticked opt-in with clear language about message frequency.