Winning a customer with ads is expensive. Bringing them back costs much less. Email and SMS are the main tools online stores use to turn first-time buyers into repeat customers. This guide covers the core flows, timing and the consent rules you need to respect.
Messaging laws vary by country and change over time. Check the rules that apply to you and consult a legal adviser if unsure.
Why Retention Matters
If you only sell once to each customer, you must keep paying to find new ones. Repeat customers lower your average acquisition cost over time and improve profit. See CPL vs CAC vs ROAS for how to measure it.
Core Flows to Set Up
| Flow | When it sends | Goal |
|---|---|---|
| Welcome series | After signup | Introduce your brand and encourage a first purchase |
| Abandoned cart | Shortly after someone leaves a cart | Remind and remove worries |
| Browse abandonment | After viewing products without adding | Bring them back to what they liked |
| Order confirmation and shipping updates | After purchase | Build trust |
| Post-purchase | After delivery | Usage tips, review request, cross-sell |
| Replenishment | When a product is likely running out | Repeat orders |
| Win-back | After a long quiet period | Re-engage lapsed customers |
Email or SMS?
- Email is good for longer content, product stories and regular updates.
- SMS is short, immediate and suited to time-sensitive messages such as delivery updates or limited offers. Use it sparingly.
Consent and Compliance Basics
- Get clear permission before sending marketing messages
- Explain what people sign up for
- Include an easy unsubscribe or opt-out
- Follow the laws for your market, such as CAN-SPAM and TCPA in the USA, UK rules on electronic marketing, Canada’s CASL and Australia’s Spam Act. Verify current rules with official sources.
Timing and Frequency
- Send helpful, relevant messages rather than daily blasts
- Segment by behavior: new customers, repeat buyers, browsers
- Test send times and subject lines
Metrics to Track
- Revenue from email and SMS flows
- Repeat purchase rate
- Unsubscribe and complaint rates
- Cart recovery rate
Frequently Asked Questions
How big does my list need to be?
Start with what you have. Even a small list benefits from welcome and cart flows.
Do I need both email and SMS?
No. Start with email, then add SMS for specific moments if your audience is open to it.
The Bottom Line
Set up the core flows, respect consent and measure repeat purchases. See our e-commerce marketing or book a free strategy call.
Disclaimer: This article is for general information only and is not legal, medical or compliance advice. Prices, features, policies, laws and results can change or may not apply to your situation, and we do not guarantee accuracy, outcomes or future performance. Please verify important details, including pricing, regulations and commitments, with the official source or website, or a qualified professional, before acting on them.