START HERE · Published 2026-10-06 · Updated 2026-10-06 · SecureSMTP
Overview
What SecureSMTP does, how you connect to it, and where to go next.
SecureSMTP sends your website’s and your app’s email and delivers it to the inbox. It also runs your contact forms: it stores each submission, emails it to you, and stops spam before it reaches your inbox.
Four ways to connect
| Way | Use it for | Start here |
|---|---|---|
| WordPress plugin | Every email WordPress sends (wp_mail), plus forms built in the dashboard. | WordPress plugin |
| REST API | Any app or site that can make an HTTPS request: Node, Python, PHP, Go, Ruby and so on. | Quickstart |
| SMTP | Apps and platforms that only let you enter an SMTP server: host, port, username and password. | SMTP |
| MCP server | AI assistants such as Claude and Cursor sending email for you. | MCP server |
Every way uses the same key: each site has one API key. It goes in a header for the API, in the WordPress plugin’s settings, or in the password field for SMTP.
How it fits together
- Site. Everything belongs to a site — usually one website or one app. Each site has one API key. See Sites and API keys.
- Sender mode. New accounts send from their own verified domain (domain mode): mail goes out from your address. Test emails to yourself, and accounts still in the grace period, go out from
[email protected]with your site’s name as the sender name (relay mode). See Your own domain is required and Domains and DNS. - Checks before sending. Each email is checked for spam content, suppressed addresses and unsubscribes before it leaves. A site’s first email is also always checked by the AI. See Deliverability.
- Events after sending. Delivered, bounced, opened, clicked and complaint events show in the email log and can be posted to your server. See Webhooks.