Best Temp Mail APIs for Developers in 2026
A developer's honest comparison of every disposable email API worth considering.
Whether you're building AI agents, running QA tests, or automating account creation, you need a disposable email API. Here's how the top services compare in 2026.
Comparison Table
| Feature | SandMail | AgentMail | Mailinator | Lumbox |
|---|---|---|---|---|
| Starting price | Free | Free | $99/mo | Free |
| Paid from | $19/mo | $20/mo | $99/mo | $19/mo |
| OTP extraction | 15 languages | AI-powered | No | Yes |
| Wait/long-poll | Yes (60s) | Yes | No | Yes |
| Webhooks | HMAC-signed | Yes | Yes | Yes |
| Email forwarding | Yes | No | No | No |
| Built-in domains | 7 | 1 | Custom only | 1 |
| MCP server | Yes | Yes | No | Yes |
| Send emails | No | Yes | Yes | Yes |
| SDKs | npm, pip, CLI | Python, TS | REST only | npm |
When to Choose Each
SandMail — Best for AI agents and automation
Choose SandMail if you need OTP extraction in multiple languages, the wait-for-OTP combo endpoint, or email forwarding. It's the most affordable option with 7 built-in domains for rotation (harder to block). The MCP server makes it plug-and-play with Claude and Cursor.
AgentMail — Best for two-way email agents
Choose AgentMail if your agent needs to send emails, not just receive. Their AI-powered parsing and threading support make it ideal for agents that manage ongoing email conversations. More expensive ($20/mo minimum) but more capable for complex workflows.
Mailinator — Best for enterprise QA testing
Choose Mailinator if you're an enterprise team that needs SMS testing alongside email. No OTP extraction, no wait endpoints, but battle-tested since 2003. Expensive at $99/mo minimum.
Lumbox — Best budget alternative
Choose Lumbox if you want a cheaper AgentMail alternative. Similar features at $19/mo. Newer, smaller community.
Verdict
For most developers building AI agents or automation pipelines in 2026, SandMail offers the best value: free tier, OTP extraction in 15 languages, wait endpoints, webhooks with OTP included, email forwarding, 7 domains, and MCP support — all at $19/mo for the paid tier.