Both channels work. The question is which works better for your specific customer relationship, and whether combining them is worth the effort.
SMS: higher open rates, faster action
Text messages have open rates above 90%, compared to around 20-30% for email. Most texts are read within 3 minutes of delivery. For a review request, that means a customer sees your message while the experience is still fresh — which is exactly when they are most likely to act. The downside is that SMS feels intrusive to some customers if you do not have an established relationship, and some industries have stricter compliance requirements around text messages.
Email: more control, works for complex messages
Email allows more context and formatting. You can include the customer's name, reference their specific service, and give clearer instructions with a button. Email also reaches customers who prefer not to share their phone number. Response rates are lower than SMS, but email review requests still outperform no follow-up at all by a wide margin.
The combination approach
The highest-performing review collection systems send an email first, then a short SMS follow-up 3 to 5 days later. The email sets context and the text converts. Customers who respond to the email never get the text. This approach captures both the fast responders and the people who need a second nudge.
Which to start with
If you have customer phone numbers, start with SMS — the faster results are motivating and the setup is simpler. Add email as a second channel once the SMS process is running smoothly.
Cost and deliverability trade-offs
There is a practical difference beyond open rates. Email is essentially free to send at any volume, which makes it ideal for large customer lists and for businesses on tight margins. SMS carries a small per-message cost and tighter regulatory requirements, but it buys you the dramatically higher open rate. For most businesses the math favors using SMS for the moments that matter most (the immediate post-service ask) and email for breadth and follow-up. Watch your SMS volume if you are cost-sensitive — but remember that a single new customer won from a review usually pays for thousands of texts.
Matching channel to your customer relationship
The right channel also depends on how your customers already interact with you. A med spa or salon that texts appointment reminders has an established SMS relationship, so a review text feels natural. A B2B service that communicates entirely over email should lead with email. A retail shop that only has email addresses from loyalty signups uses email by default. Meet customers on the channel they already associate with your business — a review request that arrives the same way your other communication does feels expected rather than intrusive.
The sequence that captures the most reviews
The highest-converting setup is not "SMS or email" — it is a timed sequence. Send the first request on the channel most likely to be seen quickly after service (usually SMS for in-person businesses, email for online ones). Then, for anyone who has not responded, send one follow-up on the other channel a few days later. Using two channels staggered over several days reaches both the instant responders and the people who needed a different nudge — and consistently outperforms relying on either channel alone.
Compliance note: Always get explicit consent before sending marketing SMS messages. Use an opt-in at the point of service or purchase, and include an opt-out. SnappyRatings handles both channels and opt-outs automatically. Run email and SMS review requests together →