Email marketing is one of the best ways to build passive income online. Unlike social media, where posts disappear fast, emails land directly in your customer’s inbox. With the right tool, you can set up automations that run on autopilot, nurture leads, and drive sales while you sleep.
In this post, we’ll cover the top three email marketing tools in 2025: Omnisend, Mailchimp, and Klaviyo. Each one is great for different types of businesses, so let’s break them down.
1. Omnisend – Best for Ecommerce Stores
If you run an ecommerce store on Shopify or WooCommerce, Omnisend is built for you.
Key Features
- Pre-built automations: Welcome series, abandoned cart reminders, and post-purchase follow-ups.
- SMS integration: Combine email with text messages in the same workflow.
- Drag-and-drop builder: No coding required to create professional emails.
Why It Works for Passive Income
With Omnisend, you can set up automated workflows that drive revenue without ongoing work. For example, if a customer abandons their cart, Omnisend automatically sends a reminder with a discount. You don’t lift a finger, yet you recover lost sales.
This makes it ideal for ecommerce brands that want to grow while focusing on other parts of the business.
2. Mailchimp – Best for Beginners and Small Businesses
If you’re new to email marketing, Mailchimp is one of the easiest platforms to start with. It works well for bloggers, coaches, or small business owners who want simple automation.
Key Features
- User-friendly interface: Drag-and-drop email templates anyone can use.
- Basic automations: Welcome emails, simple sequences, and regular newsletters.
- Analytics dashboard: See open rates and click-through rates at a glance.
Why It Works for Passive Income
Mailchimp makes it simple to send evergreen content, digital products, or course updates. Even if you only set up a 3–5 email sequence, you can nurture new subscribers into paying customers.
It’s not as advanced as other tools, but for beginners, it’s a low-barrier way to get started and generate passive income online.
3. Klaviyo – Best for Advanced Personalization
For growing ecommerce brands, Klaviyo is a powerhouse. It’s all about data-driven marketing and personalization.
Key Features
- Detailed customer profiles: Track browsing history, purchase behavior, and engagement.
- Real-time segmentation: Send targeted campaigns based on actions customers take.
- AI optimization: Helps improve deliverability and send emails at the best times.
Why It Works for Passive Income
Klaviyo lets you create highly personalized automations that feel one-to-one. For example, if a customer buys shoes, Klaviyo can automatically recommend socks or related products in the next email.
This increases repeat purchases and builds loyalty, which is key to scaling passive income in ecommerce.
Which One Should You Choose?
- Use Mailchimp if you’re just starting and want something easy to use.
- Use Omnisend if you run an ecommerce store and want smart automations with SMS.
- Use Klaviyo if you’re scaling a brand and need advanced personalization.
Each of these tools can generate passive income when set up correctly. The key is to create automated workflows that nurture, sell, and upsell without constant input.
Final Thoughts
Email marketing is still one of the most powerful ways to make money online in 2025. By choosing the right tool and setting up automations, you can build systems that sell products or services for you 24/7.
Start with where you’re at: beginners can try Mailchimp, ecommerce stores should lean into Omnisend, and scaling brands can unlock Klaviyo’s power. The earlier you build your email system, the sooner you’ll enjoy consistent, passive income.