# Request for Outgoing SMTP IP Address – Brevo SMTP Authentication Error **URL:** \ **Category:** Hosting Support\ **Created:** [October 13, 2026, 8:22am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308 "2026-10-13T08:22:08Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![IzzuDev](https://forum.infinityfree.com/letter_avatar/izzudev/32/5_5575768a8748004e209b776fc1b2916d.png) [@IzzuDev](https://forum.infinityfree.com/u/IzzuDev)\ **Post date:** [October 13, 2026, 8:22am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308/1 "2026-10-13T08:22:08Z")
### Website URL [https://sanssa.page.gd](https://sanssa.page.gd) ### Error Message My website successfully connects to Brevo and establishes TLS encryption, but authentication fails with the following error: 525 5.7.1 Unauthorized IP address ### Other Information I am hosting my website, sanssa.page.gd, on InfinityFree, and I am trying to configure email delivery for my PHP application using Brevo SMTP. My SMTP configuration is: SMTP Host: [smtp-relay.brevo.com](http://smtp-relay.brevo.com) SMTP Port: 587 Encryption: STARTTLS Could you please help me with the following? Confirm the outgoing public IP address used by my hosting account when connecting to external SMTP services. Confirm whether this outgoing IP address is shared, static, or dynamic. Advise whether my hosting account permits outgoing SMTP connections to external email providers such as Brevo. Explain whether there are any hosting restrictions that could cause this authentication error. I need this information to determine whether I can authorize the correct IP address in my Brevo account. Thank you for your assistance. ---
**Author:** ![system](https://infinityfree-forum-uploads.s3.dualstack.eu-central-1.amazonaws.com/original/3X/b/0/b024fd3fa88bae093c9576e55c2c94e33f890206.svg) [@system](https://forum.infinityfree.com/u/system)\ **Post date:** [October 13, 2026, 8:22am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308/2 "2026-10-13T08:22:08Z")
Welcome to the InfinityFree community forum! Good to have you here. - Most people answering here are volunteers. They’re often the fastest source of help. Admin (the only staff member) checks in about once a day for issues on our end. - Volunteers can’t see your account or website. Share what you actually see, like error messages and what happens when you try something. That’s more useful than your theory of what’s wrong. - AI tools often get InfinityFree wrong. If a volunteer’s advice differs from what an AI told you, please try the volunteer’s suggestion first. - Solving an issue is a joint effort. Try the suggestions you get and report back what happened. ---
**Author:** ![InfinityFreeBot](https://forum.infinityfree.com/user_avatar/forum.infinityfree.com/infinityfreebot/32/3715_2.png) [@InfinityFreeBot](https://forum.infinityfree.com/u/InfinityFreeBot)\ **Post date:** [October 13, 2026, 8:22am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308/3 "2026-10-13T08:22:20Z")
_Beep boop, I’m a bot! I dug through the forum to get you started. I sometimes get things wrong though, so do with this what you will until a human has a look._ I couldn’t find anything that confirms the outgoing IP address for your account, or whether it’s shared, static or dynamic. I can’t give you an address to authorize in Brevo. That part needs a person to look. On your SMTP question, our article on sending email says InfinityFree doesn’t restrict sending email through external providers, and that includes SMTP. The restriction is on PHP’s `mail()` function, not on SMTP to outside services: > [@How to send email with Gmail SMTP](https://forum.infinityfree.com/docs?topic=49239): > > Outgoing email with PHP mail() is heavily restricted on InfinityFree. Fortunately, you can still whatever email you want using an external email service. There are many external email providers to choose from. InfinityFree doesn’t restrict sending email with external providers. Almost all of them have paid plans, but some have free tiers too. Most of them support sending email over SMTP, some of them have custom APIs, libraries and plugins which you can use too. A simple way to get started qui… Your connection and the TLS handshake worked, and the 525 reply came back after that. That suggests Brevo is the one rejecting the login because the connecting IP isn’t on your allowed list. I can’t tell from the article whether anything on our side affects that. ---
**Author:** ![IzzuDev](https://forum.infinityfree.com/letter_avatar/izzudev/32/5_5575768a8748004e209b776fc1b2916d.png) [@IzzuDev](https://forum.infinityfree.com/u/IzzuDev)\ **Post date:** [October 13, 2026, 8:27am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308/4 "2026-10-13T08:27:18Z")
Thank you for your response. I understand that the connection and TLS handshake are successful, but Brevo rejects the authentication with 525 5.7.1 Unauthorized IP address. Could a human support team member please help me determine the outgoing public IP address used by my hosting account when connecting to external SMTP services? I need to know whether this IP address is shared or dynamic so I can determine whether it can be authorized in Brevo. My website is sanssa.page.gd. Thank you. ---
**Author:** ![Meishin](https://forum.infinityfree.com/user_avatar/forum.infinityfree.com/meishin/32/59902_2.png) [@Meishin](https://forum.infinityfree.com/u/Meishin)\ **Post date:** [October 13, 2026, 8:32am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308/5 "2026-10-13T08:32:19Z")
> [@system](#): > > - Admin (the only staff member) checks in about once a day for issues on our end. > - Volunteers can’t see your account or website. If you absolutely need staff check your website then you’ll have to wait. ---
**Author:** ![dan3008](https://forum.infinityfree.com/user_avatar/forum.infinityfree.com/dan3008/32/53336_2.png) [@dan3008](https://forum.infinityfree.com/u/dan3008)\ **Post date:** [October 13, 2026, 8:36am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308/6 "2026-10-13T08:36:42Z")
Might be worth reading this guide though in the interim > [@Send Emails for Free with Brevo (formerly Sendinblue)](https://forum.infinityfree.com/t/send-emails-for-free-with-brevo-formerly-sendinblue/71921): > > This tutorial would show you how to send emails with Brevo (formerly Sendinblue). You can create unlimited emails and send up to 300 emails per day. Brevo (formerly Sendinblue) is an SMTP server that sends email for applications. You can send up to 300 emails/day with Brevo. Even though it says they will add Brevo branding on their site, that is only if you use their email marketing tool and not their SMTP service. Create an account with Brevo (or sign in with google) Go to profile and se… ---
**Author:** ![Admin](https://forum.infinityfree.com/user_avatar/forum.infinityfree.com/admin/32/36437_2.png) [@Admin](https://forum.infinityfree.com/u/Admin)\ **Post date:** [October 13, 2026, 11:25am UTC](https://forum.infinityfree.com/t/request-for-outgoing-smtp-ip-address-brevo-smtp-authentication-error/121308/7 "2026-10-13T11:25:30Z")
I just wrote a response to what is basically the same question someone asked yesterday. > [@Fixed outbound public IP used by PHP cURL requests when my website connects to an external server](https://forum.infinityfree.com/t/fixed-outbound-public-ip-used-by-php-curl-requests-when-my-website-connects-to-an-external-server/121289/5): > > The IP addresses are 100% shared. We host hundreds of thousands of websites completely for free, and using a different IP address for every single one is both crazy expensive and completely unnecessary. I don’t know exactly how the external IPs are set up. I don’t think they change often. I know that they are not the same as your Website IP, and I think the best way to find the right IP is to use a bit of PHP code to grab it from an IP lookup tool, e.g. \