Customer.io vs Klaviyo
Customer.io and Klaviyo are both popular choices in the email marketing platform space. Klaviyo is the more affordable option at $20/mo — that's $80 less per month than Customer.io's $100/mo entry point. Klaviyo offers a free plan (250 subscribers), while Customer.io does not. Klaviyo has the edge with landing pages, ecommerce integrations.
Quick Verdict
Klaviyo wins on price, deliverability, rating, integrations, free tier.
Best for most users: Klaviyo (ecommerce).
Customer.io
Behavioral messaging platform for product-led SaaS and tech companies
Customer.io is a behavioral messaging platform built for product-led SaaS companies that need to trigger automated emails, SMS, push notifications, and in-app messages based on real-time user events. Its visual workflow builder and Liquid templating provide deep personalization, while the built-in Data Pipelines act as a lightweight CDP. Trusted by 8,000+ companies including Notion and Segment, it starts at $100/month for 5,000 profiles.
Klaviyo
The platform for unified customer data
Klaviyo is the gold standard for ecommerce email and SMS marketing, particularly for Shopify stores. Its deep integration with ecommerce platforms enables sophisticated automated flows like abandoned cart, post-purchase, and win-back sequences based on real purchase data.
Feature Comparison
| Feature | Customer.io | Klaviyo |
|---|---|---|
| Rating | 4.4/5 | 4.6/5 |
| Starting Price | $100/mo | $20/mo |
| Free Plan | No free plan | 250 subscribers |
| Founded | 2012 | 2012 |
| Email Templates | 30 | 100 |
| Integrations | 150 | 350 |
| Deliverability Rate | 96% | 99% |
| Marketing Automation | ✓ | ✓ |
| A/B Testing | ✓ | ✓ |
| Landing Pages | ✕ | ✓ |
| Segmentation | ✓ | ✓ |
| Drag & Drop Editor | ✓ | ✓ |
| SMS Marketing | ✓ | ✓ |
| Ecommerce Features | ✕ | ✓ |
| API Access | ✓ | ✓ |
| Multi-Language | ✓ | ✓ |
| Web Push Notifications | ✓ | ✕ |
| Live Chat | ✕ | ✕ |
| Advanced Analytics | ✓ | ✓ |
Customer.io: Pros & Cons
Pros
- +Powerful visual workflow builder with real-time event-based triggers for behavioral automation
- +Omnichannel messaging across email, SMS, push notifications, in-app, and webhooks in one platform
- +Built-in Data Pipelines that serve as a lightweight CDP, unifying web, mobile, and backend data
- +Segment builder is intuitive enough for marketers without requiring dedicated engineering support
- +Startup Program offers up to 12 months free for qualifying early-stage companies
Cons
- −Essentials plan starts at $100/month for only 5,000 profiles — expensive for small teams
- −Steep learning curve for non-technical users, especially with Liquid templating syntax
- −Pricing scales aggressively past 10K profiles with significant jumps between plan tiers
- −Template editor feels restrictive for highly custom-coded email layouts
- −Searching for past messages and editing templates can be unintuitive and slow
Klaviyo: Pros & Cons
Pros
- +Best-in-class ecommerce integrations (Shopify, WooCommerce)
- +Powerful segmentation with predictive analytics
- +Excellent deliverability (99%+)
- +Revenue attribution for every email and SMS
- +Deep customer data platform capabilities
Cons
- −Expensive for large lists
- −Steep learning curve
- −Free plan very limited (250 contacts)
- −SMS credits sold separately
- −Can be overkill for non-ecommerce businesses
The Verdict
Customer.io and Klaviyo are closely matched — both score within 0.2 points of each other in our overall rating. Your decision should come down to specific needs rather than overall quality. On deliverability, Klaviyo reports 99% compared to 96% for Customer.io — a meaningful difference if inbox placement is critical for your campaigns.
| Criterion | Weight | Customer.io | Klaviyo |
|---|---|---|---|
| Starting Price | 30% | $100/mo | $20/mo |
| Deliverability | 25% | 96% | 99% |
| Rating | 25% | 4.4/5 | 4.6/5 |
| Integrations | 10% | 150 | 350 |
| Free Tier | 10% | No | Yes |
Weights determine how much each criterion counts toward the final score. See full methodology
Choose Customer.io if…
- + You're a product led saas companies with event driven messaging needs
- + You're a technical marketing teams that want advanced automation with liquid logic
- + Powerful visual workflow builder with real-time event-based triggers for behavioral automation
Choose Klaviyo if…
- + You want lower starting costs ($20/mo)
- + You need a free plan to get started
- + You need ecommerce integrations
- + You need built-in landing pages