IP addresses and ports

Overview

Some organisations operate security policies that deny outbound traffic by default. If your organisation does this, you’ll need to add Mailosaur’s services to your allowlist.

We may change to our IP addresses from time to time, and so we recommend allowing by domain name rather than IP address whereever possible.

Domains and IP addresses

Mailosaur is accessible via three primary IP addresses: 34.149.187.159, 35.187.177.145 and 35.233.95.121:

Note that the Legacy SMTP & POP3 services only apply to customers connecting to mailosaur.io in their test code.

Port numbers

For services to function, you must allow the following TCP ports: