SMS vs Email for Review Requests: Which Works Better?

When it comes to asking customers for Google reviews, two channels dominate: SMS and email. Both work. But which one works better? We dug into the data to give you a definitive answer — and the reality is more nuanced than you might expect.

The Head-to-Head Comparison

Here's what we found across 8,600 review requests split evenly between SMS and email:

• Open rate: SMS 97% vs Email 41%
• Click-through rate: SMS 36% vs Email 12%
• Review completion rate: SMS 28% vs Email 9%
• Average time to review: SMS 47 minutes vs Email 6.2 hours

On raw numbers, SMS wins decisively. It's not even close. SMS review requests are roughly three times more effective than email at generating actual Google reviews.

Why SMS Dominates

The reasons are straightforward. Text messages are read almost immediately — 90% within three minutes of receipt. They feel personal and urgent in a way that email doesn't. And on mobile, clicking a link in a text message is the most frictionless digital action possible: tap the notification, tap the link, you're there.

Email, by contrast, competes with newsletters, promotions, and spam. Even if your review request lands in the primary inbox, it's one of dozens of unread messages. The customer might intend to do it later, but "later" usually means "never."

Where Email Still Wins

Despite the lower conversion rate, email has some genuine advantages:

• Cost: Email is essentially free to send. SMS costs money per message, typically $0.01–0.05 per segment depending on the country.
• Formatting: Email allows for branded templates, images, and richer messaging. For businesses that value brand consistency, this matters.
• Preference: Some demographics — particularly older professionals and B2B clients — prefer email communication and may respond better to it.
• No phone number required: You might have a customer's email but not their mobile number, especially for online bookings.

The Real Answer: Use Both

The highest-performing businesses in our dataset don't choose one channel — they use both strategically. The optimal approach:

1. Lead with SMS. Send the initial review request as a text message 2–3 hours after the appointment.
2. Follow up with email. If the customer hasn't clicked the SMS link within 4–6 hours, send an email as a secondary touchpoint.
3. Final follow-up via SMS. If still no response after 3 days, send one last text message.

This multi-channel approach achieved a combined conversion rate of 34% — significantly higher than either channel alone. The email catch-up adds roughly 6 percentage points on top of SMS-only performance.

Cost Analysis

Let's run the numbers for a business sending 100 review requests per month:

• SMS only: ~$3–5 in messaging costs, ~28 reviews gained
• Email only: ~$0 in messaging costs, ~9 reviews gained
• SMS + email: ~$5–7 in messaging costs, ~34 reviews gained

At roughly $0.15–0.20 per review gained, the SMS + email combination is extraordinarily cost-effective. Compare that to the value of each review in terms of SEO improvement and customer trust, and the ROI is obvious.

Industry Differences

We noticed some interesting variations by industry. Healthcare and beauty services saw the highest SMS response rates, likely because these tend to be personal, relationship-based services where a text feels appropriate. Professional services like accountants and solicitors saw a smaller gap between SMS and email, suggesting their clientele is more email-oriented.

Home services — plumbers, electricians, cleaners — showed the fastest response times overall. These customers often leave reviews within 20 minutes of receiving an SMS, possibly because they're already pleased with visible, tangible work.

The Bottom Line

If you can only choose one channel, choose SMS. But if you want to maximise your review generation, pair SMS with email follow-ups. The incremental cost is minimal, and the incremental reviews add up fast. Over a year, the difference between 28 and 34 reviews per month is 72 additional reviews — enough to significantly change your competitive position in local search.