How to Include Testimonials in Your Email Marketing Strategy

Why Testimonials Belong in Your Emails

Email marketing remains one of the highest-ROI marketing channels available, delivering an average return of 36 dollars for every dollar spent. Yet many email marketers focus exclusively on crafting compelling copy and eye-catching designs while overlooking one of the most powerful elements they could include: customer testimonials.

Testimonials in emails serve the same trust-building function they serve on your website, but with an added advantage: they reach your audience directly in their inbox, where the environment is personal and intimate. A testimonial in an email does not compete for attention with dozens of other elements on a web page. It arrives in a focused, one-to-one context where the reader is more receptive to its message.

Research shows that emails containing social proof elements like testimonials see 15-20% higher click-through rates than emails without. In sales-focused email sequences, testimonials can increase conversion rates significantly by providing the third-party validation that helps recipients make their purchase decision.

Types of Email Campaigns That Benefit from Testimonials

Welcome Sequences

Your welcome email sequence is where new subscribers form their first impression of your brand. Including a testimonial in the second or third email of the sequence helps build trust early in the relationship. Choose a testimonial that speaks to the overall value of your product or service and the satisfaction of being a customer.

For example, after introducing your brand and its story in email one, email two might share a customer story: "Meet Sarah, who started using our platform last year and increased her conversion rate by 35%." This introduces social proof before any sales pitch, establishing credibility that primes the subscriber for future offers.

Sales and Promotional Emails

When you are making a direct offer, whether it is a product launch, a special promotion, or a seasonal sale, testimonials add credibility to your claims. Include a relevant testimonial below your offer description and above your call-to-action button. The testimonial should address the specific value proposition of your offer.

For instance, if you are promoting a limited-time discount, a testimonial like "I signed up during the last sale and it has been the best investment I made all year. Do not hesitate like I almost did" creates urgency through a peer's experience.

Abandoned Cart Emails

Cart abandonment emails are the perfect vehicle for testimonials because the recipient has already shown purchase intent. They were interested enough to add items to their cart but hesitated at the last moment. A testimonial in the abandoned cart email directly addresses whatever doubt caused them to leave.

"I almost did not complete my purchase, but I am so glad I did. The product arrived quickly and exceeded my expectations." This type of testimonial mirrors the recipient's situation and provides the reassurance they need to return and complete the purchase.

Onboarding Emails

For SaaS and subscription businesses, onboarding emails guide new users through the product experience. Including testimonials from users who successfully completed onboarding reinforces the value of continuing through the process. "The setup took me less than 30 minutes, and I was seeing results by the end of the first week" motivates new users to stay engaged during the critical onboarding period.

Re-engagement Campaigns

When trying to win back inactive subscribers or lapsed customers, testimonials remind them of the value they are missing. "I stopped using the platform for a few months and could immediately see the difference in my results. Coming back was the best decision." This type of testimonial speaks directly to someone who has already experienced the product and left.

Newsletter Content

Your regular newsletter is an excellent vehicle for sharing customer stories. Dedicate a section to a "Customer Spotlight" or "Success Story" that features a different customer each edition. This provides ongoing social proof to your subscriber base and creates content variety that keeps newsletters interesting.

Formatting Testimonials for Email

Email is a constrained medium with different design requirements than a web page. Here is how to format testimonials effectively for email:

Keep it short: Email testimonials should be one to three sentences maximum. Readers scan emails quickly, and a long testimonial will be skipped. If you have a compelling long-form story, include a teaser with a "Read the full story" link to your website.

Use visual formatting: Make the testimonial visually distinct from the rest of the email content. Use italics, a background color, quotation marks, or a bordered box to set it apart. This ensures the reader notices it even during a quick scan.

Include a face: Add the customer's headshot alongside their testimonial. A face makes the testimonial personal and credible, even in the compact email format. Keep the image small, around 50-60 pixels in diameter, to avoid layout issues.

Add context: Below the testimonial, include the customer's name, title, and company or location. This context adds credibility and helps the reader identify with the testimonial author.

Link to more: If you have a comprehensive testimonials page or Wall of Love, include a text link "See what 200+ customers say about us" that takes readers to the full display. This serves both as social proof and as a way to drive website traffic.

Subject Lines That Leverage Social Proof

Your email subject line is the most important factor in determining whether the email gets opened. Subject lines that reference social proof or customer experiences can significantly boost open rates. Examples include:

• "How [Customer Name] increased sales by 47%"
• "See why 500+ businesses trust us"
• "[Customer]: 'This changed everything for my business'"
• "The results our customers are seeing this month"
• "What our top customers do differently"

These subject lines create curiosity and leverage the credibility of real customer experiences to motivate opens.

Email Testimonial Placement Best Practices

Where you place a testimonial within the email affects its impact. The three most effective positions are:

After the pitch, before the CTA: This is the classic position. You present your offer, provide a testimonial that validates the offer, and then present the call to action. The testimonial serves as the final reassurance before the reader makes their decision.

As the opening hook: Start the email with a customer quote or story. "When Maria switched to our platform, she was skeptical. Three months later, her conversion rate had doubled." This immediately engages the reader with a real story rather than a sales pitch.

As a P.S. element: The P.S. line is one of the most-read parts of any email. A brief testimonial in the P.S. section catches readers who scroll to the end without reading the middle. "P.S. As our customer David says, 'I wish I had started sooner.' Do not make the same mistake."

Measuring Testimonial Impact in Emails

Track these metrics to understand how testimonials affect your email performance:

• Open rate: Compare subject lines with social proof versus without. This measures the top-of-funnel impact of testimonial-referenced subject lines.
• Click-through rate: Compare CTR in emails with testimonials versus without. This measures the mid-funnel persuasion effect.
• Conversion rate: Track how many email recipients who read the testimonial ultimately convert. This is the bottom-line metric.
• Revenue per email: Calculate the average revenue generated per email for campaigns with and without testimonials to quantify the financial impact.

Building a Testimonial-Rich Email Strategy with Opinafy

Opinafy provides a centralized library of customer testimonials that you can easily search and select from when building email campaigns. The platform organizes testimonials by topic, industry, and outcome, making it quick to find the perfect testimonial for each email. Combined with Opinafy's collection tools that continuously bring in fresh testimonials, you always have current, compelling social proof ready for your next campaign.

Conclusion: Every Email Is a Trust Opportunity

Every email you send is an opportunity to build trust with your audience. By integrating customer testimonials into your email strategy, you transform routine marketing messages into trust-building communications that drive measurably higher engagement and conversions.

Start with a single experiment: take your next sales email and add one customer testimonial above the CTA. Measure the results. Then expand from there, incorporating testimonials into your welcome sequence, abandoned cart emails, newsletters, and re-engagement campaigns. With Opinafy, your testimonial library is always at your fingertips. Start free today.