New channels grab the spotlight — think influencers, streaming, and AI-everything. But one channel still outperforms when it comes to reliable revenue: email. For affiliate managers, publishers, and brands, it remains a foundational tool that drives measurable results.
Explore the seven reasons this “old-school” channel powers modern affiliate success in 2025.
1. Email (Still) Rules ROI
Nearly 4.6 billion people use email daily, generating around 376 billion emails per day in 2025.
Email delivers an outstanding return-on-investment: around $15 for every $1 spent.
These powerful numbers mean that email-based affiliate offers reach deeply engaged audiences who expect, and open, relevant, well-timed content.
2. Owned Audiences Convert Better
Unlike fleeting social media audiences, email lists are owned by you and offer persistent access. Industry benchmarks show that affiliate links in email news content can convert at 2-3%, doubling standard web traffic conversion rates.
Brands and affiliate networks love this because each subscriber is an active audience primed for affiliate offers, such as seasonal deals, new product launches, or re-engagement campaigns.
3. Affiliate Programs Drive Big Dollars
The affiliate marketing industry continues to boom. 2025 affiliate spend is projected to pass $37 billion, about a 14% increase from 2024.
In the U.S. alone, affiliate spending is expected to reach $12 billion in 2025. And on top of that, affiliate programs already drive roughly 16% of all U.S. e‑commerce orders.
That means nearly one in six online purchases is fueled by affiliate links. And email remains the secret weapon, powering much of that pipeline by nurturing intent and confidence.
4. Email Plays Nice with Other Affiliate Channels
Email amplifies other affiliate marketing channels. Some examples:
- Blogs: Follow-up emails with direct affiliate links after blog visits
- Video: Email reminders for limited-time discounts promoted during live streams or in chat
- Influencers: Email-exclusive codes or deep-dive product recommendations for subscribers
Multi-channel affiliate programs, anchored by email, deliver better reach, repetition, and conversions.
5. It’s Measurable and Personal
Modern email platforms offer deep analytics and personalization tools. Segment subscribers by past purchases, click behaviors, device, and location. Automate targeted affiliate sequences like welcome flows, cart reminders, and re-activation series.
These tactics aren’t just smart; they’re expected and effective. And they keep delivering ROI long after the send.
6. Affordability and Ease of Execution
Compared to costly paid media, email is fast, low-cost, and runs on automation tools. Marketers of any skill level can add affiliate links directly in campaigns, no complex integrations necessary.
This makes email a scalable, flexible channel for launching and optimizing promotions for brands in a wide variety of verticals.
7. The Trust Factor
Even as new channels arise, email remains trusted, familiar, and permission-based. Subscribers proactively sign up, opt in, and expect content. Affiliate offers in email feel organic, not like ads shoved into feed.
And if the recipient didn’t provide consent to be contacted? Opting out is usually easy, and the email sender can face strict fines and consequences thanks to new global regulations.
That trust drives open rates of 15-25% and click-through rates of 3-8% when segmented well.
Takeaways for Affiliate Success
Make email central
Build and segment lists with affiliate intent in mind: welcome series, interest-based segments, frequent buyers.
Blend content with offers
Create longform emails with storytelling and strategically placed affiliate links that feel natural.
Automate smart flows
Use triggers (welcome, site visit, category interest, etc.) to launch timely affiliate campaigns.
Test constantly
A/B subject lines, segment-based offers, customized deal types, and more built on data will drive better results.
Track and attribute
Use tracked links and integrated dashboards to measure email affiliate performance accurately.
The Final Word
In 2025, email marketing is a fundamental part of strategic affiliate programs. It remains not just relevant, but essential. With razor‑sharp targeting, strong ROI, and near-universal reach, email underpins nearly every successful affiliate campaign today. Pair it with content, influencers, and paid channels, and you’re on the way to a successful campaign in no time.
So while the industry continues to evolve toward AI chatbots, influencer livestreams, and immersive shopping experiences, don’t overlook email. It’s still the foundation — and in many cases, the highest-performing piece — of your affiliate marketing mix.