You have two channels for reaching past customers: SMS and email. They behave very differently — and the right answer for your reactivation campaign depends on your list, your service, and your goals.
Open rates: SMS wins clearly
SMS messages have an average open rate of 95%+ and are typically read within 3 minutes of receipt. Email open rates for service business marketing emails run 15–25%. For reaching customers quickly and reliably, SMS is significantly more effective.
Response rates: SMS wins again, but email has advantages
SMS response rates for well-written reactivation campaigns run 8–20%. Email response rates run 3–8%. However, email allows for longer messages, clickable links to booking pages, and visual elements — which can be useful for more complex services or offers.
Compliance considerations
Both channels require consent. For past customers who gave you their contact information for service purposes, a reactivation message is generally considered a business-to-customer service communication — not spam. Clear opt-out options (reply STOP for SMS, unsubscribe link for email) keep you compliant.
The best approach: SMS first, email follow-up
For most service businesses, send SMS first to the full list. 3–4 days later, send a follow-up email to everyone who didn't respond to the SMS. This two-channel approach consistently outperforms either channel alone and captures the different response preferences of your customer base.