Customer.io vs Klaviyo
Behavioral lifecycle automation for SaaS versus event-rich ecommerce automation.
What matters for growth and lifecycle teams
Growth work lives or dies on targeting and measurement. What matters is whether behavioral triggers can be built without engineering time, whether the event stream supports attribution past the open, and whether deliverability holds when broadcast volume shares a reputation with product email.
| Priority | Customer.io | Klaviyo |
|---|---|---|
| Scheduling | Yes | Yes |
| Event stream | Yes | Yes |
| Deliverability | Good; reputation managed at the workspace level with optional dedicated IPs. | Solid for ecommerce traffic. |
| Operating since | 2012 | 2012 |
| Suppressions API | Yes | Yes |
| Best published rate per 1,000 | Tiers not published in comparable form | Tiers not published in comparable form |
| Multi-tenant | Yes | No |
| Free tier | No permanent free tier; trial only | 500 emails to 250 contacts |
| Starts at | $100/mo (Essentials) | $45/mo for 5,000 emails |
For lifecycle and activation work running behavior-triggered journeys, broadcasts, and winback campaigns measured on revenue, Customer.io takes every priority that separates them here (multi-tenant support), while Klaviyo matches it on the rest. On free tier, Customer.io offers No permanent free tier; trial only against 500 emails to 250 contacts from Klaviyo. That ordering reflects this audience. Weigh the same table differently and the answer changes.
Side by side
| Feature | Customer.io | Klaviyo |
|---|---|---|
| Deliverability | Good; reputation managed at the workspace level with optional dedicated IPs. | Solid for ecommerce traffic. |
| Multi-tenant | Yes | No |
| Free tier | No permanent free tier; trial only | 500 emails to 250 contacts |
| Starts at | $100/mo (Essentials) | $45/mo for 5,000 emails |
| Tagline | Behavior-driven lifecycle messaging. | Ecommerce-focused marketing automation. |
| Pricing model | subscriber-based | subscriber-based |
| API | Yes | Yes |
| SMTP | No | No |
| SDKs | node, python, go, ruby, php, java | node, python, php, ruby |
| Templates | rich | rich |
| React Email | No | No |
| Webhooks | Yes | Yes |
| Inbound | No | No |
| Idempotency | No | No |
| Dedicated IP | Yes | Yes |
| DX score | 7/10 | 6/10 |
| Best for | B2B SaaS teams running complex onboarding and lifecycle programs. | Shopify and ecommerce teams. |
Customer.io
- ›Best-in-class behavioral targeting
- ›Strong workflow editor
- ›Multi-channel
- ›Expensive starting price
- ›Overkill for pure transactional
- ›Pricing scales with users
Klaviyo
- ›Ecommerce integrations are deep
- ›Predictive analytics
- ›Weak for non-ecommerce use cases
- ›Pricing climbs fast with contact growth