Home › Compare › Klaviyo vs Substack
Klaviyo vs Substack
Klaviyo: Ecommerce/B2C brands running email + SMS on customer data. Substack: Writers making money doing the work they believe in. Same fact set for both, straight from each vendor's docs.
Klaviyo
- Free tier
- Yes, up to 250 active profiles / 500 emails/mo
- Paid from
- $20/mo (email, up to 500 profiles); active-profile based · pricing page
- Public API
- Yes docs
- MCP server
- Yes · Official hosted MCP (mcp.klaviyo.com) in dev docs
- Best for
- Ecommerce/B2C brands running email + SMS on customer data
- Website
- https://www.klaviyo.com
Substack
- Free tier
- Free to publish, no subscriber cap
- Paid from
- No monthly fee; 10% of paid subscription revenue plus Stripe fees · pricing page
- Public API
- Yes docs
- MCP server
- Community · Community servers on GitHub only
- Best for
- Writers making money doing the work they believe in
- Website
- https://substack.com
Which one?
Klaviyo suits ecommerce/b2c brands running email + sms on customer data. Substack suits writers making money doing the work they believe in. Pricing changes; the fact tables above link both vendors' live pricing pages. For the rest of the field, see Klaviyo alternatives, Substack alternatives, or the full table.