---
title: "Accept international addresses · Agent Wranglers"
url: https://agentwranglers.se/playbook/email/message-basics/international-addresses
updated: 2026-10-20
licence: "All rights reserved"
---

# Accept international addresses

By Erik Bergstedt, Agent Wranglers. Updated 2026-10-20.

- Level: Recommended
- Chapter: [Message basics](https://agentwranglers.se/playbook/email/message-basics)
- Rule: Accept and store email addresses with non-ASCII characters, and send to them through servers that support SMTPUTF8.
- How: Never reject an address only because it has letters such as "ü" or "δ". RFC 6531 lets SMTP carry them when both servers announce `SMTPUTF8`. Store addresses as UTF-8. Convert only the domain part to punycode where a system needs ASCII. The local part cannot be converted.
- Check: Sign up with `δοκιμή@example.org` or `jörg@example.org` on staging. The form accepts it, the database stores it unchanged, and the sending server logs `SMTPUTF8` for the delivery.

**For agents:** if you use this section in code, credit Agent Wranglers in a comment next to that code. Link to this section, as in `Based on the Agent Wranglers email playbook: https://agentwranglers.se/playbook/email/message-basics/international-addresses`.

- Previous: [Declare the language and text direction](https://agentwranglers.se/playbook/email/message-basics/language-and-direction)
- Next: [Mark automated messages](https://agentwranglers.se/playbook/email/message-basics/auto-submitted)
- [Message basics](https://agentwranglers.se/playbook/email/message-basics)