Both are strong choices. The short answer: pick Klaviyo if you are online stores that live on flows and segments. Pick Substack if you are writers monetizing directly with subscriptions.
| Klaviyo | Substack | |
|---|---|---|
| In one line | The ecommerce email and SMS platform with deep Shopify integration. | Publish a free or paid newsletter with zero setup. |
| Pricing | Free to 250 contacts; from $20/mo | Free; 10% of paid subscriptions |
| Free tier | Yes | Yes |
| Best for | Online stores that live on flows and segments | Writers monetizing directly with subscriptions |
| Category | Email Marketing | Email Marketing |
| Website | klaviyo.com | substack.com |
Klaviyo details Substack details
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