Mails.ai vs SendGrid
Both sit in email marketing. Here is how they differ on the things you can actually check.
On price: both start at the same $20 a month. Where a price could not be read from the vendor's page it is marked indicative below.
Mails.ai
mails.ai
Gives an AI agent a real mailbox: inbound arrives as structured reply events carrying a prompt-injection score and sender reputation, with a six-category injection scanner on every message, dedicated IPs and an MCP server. Cold email is refused at the API rather than in the fine print.
SendGrid
sendgrid.com
Twilio-owned sending platform covering both transactional API traffic and marketing campaigns, built for large volumes and dedicated IP setups.
| Mails.ai | SendGrid | |
|---|---|---|
| Entry price | $20/mo | $20/mo |
| Entry plan | Pro | — |
| Paid annually | — | — |
| Price checked | 21 Sept 2026 | not verified |
| Pricing model | Free plan | Free plan |
| Free plan | Yes | Yes |
| Category | Email Marketing | Email Marketing |
| Around since | 2025 | 2009 |
1 of these 2 prices were read from the vendor's own pricing page, most recently on 21 Sept 2026; the rest are indicative. Entry tier only — vendors change pricing without notice.
Mails.ai vs SendGrid, answered
- Is Mails.ai cheaper than SendGrid?
- Neither. Both start at $20 a month at the entry tier.
- Do Mails.ai or SendGrid have a free plan?
- Both do. Mails.ai and SendGrid each publish an ongoing free tier rather than a time-limited trial.
- What is the difference between Mails.ai and SendGrid?
- Mails.ai: Gives an AI agent a real mailbox: inbound arrives as structured reply events carrying a prompt-injection score and sender reputation, with a six-category injection scanner on every message, dedicated IPs and an MCP server. Cold email is refused at the API rather than in the fine print. SendGrid: Twilio-owned sending platform covering both transactional API traffic and marketing campaigns, built for large volumes and dedicated IP setups.
