Choosing between Substack and Customer.io comes down to your specific use case. Substack is built for writers monetising directly from subscribers, while Customer.io targets product and growth teams sending behaviour-triggered messages.
| Feature | Customer.io | Substack |
|---|---|---|
| 💰 Pricing | ||
| Free Plan | ✗ | ✓ |
| Starting Price | $100/mo | Free |
| Free Trial | ✓ | ✗ |
| ⚙️ Features | ||
| Email Automation | ✓ | ✗ |
| Visual Workflow Builder | ✓ | ✗ |
| Landing Pages | ✗ | ✗ |
| Built-in CRM | ✗ | ✗ |
| SMS Marketing | ✓ | ✗ |
| A/B Testing | ✗ | ✗ |
| E-commerce Integration | ✗ | ✗ |
| Transactional Email | ✓ | ✗ |
| Remove Branding | ✓ | ✗ |
| 🤖 AI Features | ||
| AI Subject Lines | ✗ | ✗ |
| AI Send-Time Optimisation | ✗ | ✗ |
| 🛎 Support | ||
| Email Support | ✓ | ✓ |
| Live Chat | ✓ | ✗ |
| Phone Support | ✓ | ✗ |
Customer.io is best for product and growth teams sending behavior-triggered messages.
Try Customer.io Free →It depends on your use case. Substack wins for writers monetising directly from subscribers, while Customer.io is stronger for product and growth teams sending behaviour-triggered messages.
Substack starts at a lower price point. Pricing scales with subscriber count so total cost depends on your list size.
Yes, switching is possible. Most platforms support CSV import/export. Plan time to recreate automations and templates.