# Best x402 email and SMS API

As of 20 Oct 2026, the best x402 email and SMS API on Hagglyai's ranking is gateway.spraay.app: scored 79/100, $0.01 per message sent, 6 paying wallets in the last 30 days (POST https://gateway.spraay.app/api/v1/notify/email). Hagglyai compares 45 paid email and SMS APIs on price, live uptime and real usage.

| # | Service | Price per message sent | Score | Uptime 7d | Payers 30d | Endpoint |
|---|---|---|---|---|---|---|
| 1 | gateway.spraay.app | $0.01 | 79 B | 100% | 6 | `POST https://gateway.spraay.app/api/v1/notify/email` |
| 2 | Ausca Agent Inbox | $0.05 | 82 B | 100% | 19 | `POST https://ausca.com/v1/open-inbox` |
| 3 | gateway.spraay.app | $0.02 | 79 B | 100% | 6 | `POST https://gateway.spraay.app/api/v1/notify/sms` |
| 4 | AgentLine - AI Phone Service | $1 | 78 B | 100% | 4 | `GET https://api.agentline.cloud/v1/billing/topup/x402/pay` |
| 5 | BlockRun.AI | $0.541 | 77 B | 100% | 3 | `POST https://blockrun.ai/api/v1/voice/call` |
| 6 | x402.orthogonal.com | $0.01 | 76 B | 100% | 4 | `POST https://x402.orthogonal.com/agentmail/v0/inboxes/x402test1786260932@agentmail.to/messages/send` |
| 7 | FiatDock | $0.001 | 75 B | 100% | 3 | `POST https://fiatdock.com/v1/email/check` |
| 8 | Decisions (OpenAI wire) | $0.001 | 75 B | 100% | 2 | `POST https://agent402.tools/v1/decisions` |
| 9 | MarketPulse | $0.15 | 73 B | 100% | 1 | `GET https://marketpulse.theaslangroupllc.com/api/market/email-sequence` |
| 10 | Palmyr Communications | $0.08 | 72 B | 100% | 1 | `POST https://palmyr.ai/email/inboxes/:id/send` |

Listings carrying a warning (wrong price, wrong wallet, not answering) are left out. Full comparison with every listing and filter: https://hagglyai.com/compare/messaging

## Questions

### What is the best x402 email and SMS API?

As of 20 Oct 2026, the best x402 email and SMS API on Hagglyai's ranking is gateway.spraay.app: scored 79/100, $0.01 per message sent, 6 paying wallets in the last 30 days (POST https://gateway.spraay.app/api/v1/notify/email). Hagglyai compares 45 paid email and SMS APIs on price, live uptime and real usage.

### How much does an x402 email and SMS API call cost?

Across 45 paid endpoints Hagglyai tracks, prices run from $0.001 to $10 per message sent; the middle half costs $0.01 to $0.1.

### How does Hagglyai rank x402 APIs?

Hagglyai probes every paid endpoint for a valid x402 payment-required answer and scores it on 7-day uptime, speed and whether the price and wallet match the listing; usage comes from the public catalogues. Sellers cannot pay for placement. Method: https://hagglyai.com/how-we-test

### How does an agent pay for an x402 email and SMS API?

The agent calls the endpoint, gets an HTTP 402 answer with the price, signs a USDC payment with any x402 client and repeats the call. Agents can also ask Hagglyai first, over MCP (find_best) or https://hagglyai.com/api/v1/best?task=email%20and%20SMS%20API.

See also: Cheapest x402 email and SMS API: https://hagglyai.com/x402/cheapest-email-and-sms-api.md
Markdown of the full comparison: https://hagglyai.com/compare/messaging.md · JSON: https://hagglyai.com/api/v1/categories/messaging

Source: hagglyai.com/compare/messaging · as of 2026-10-20 13:10 UTC