Send email through SMTP

SMTP is the standard way programs hand email to a mail server. Choosing SMTP as your sending service lets your marketplace send its emails through almost any provider: the mailbox you already use for your domain, or a service built for sending lots of email.

Which mail server to use

• An email-sending service (Amazon SES, Brevo, Mailgun, SendGrid, Postmark…) is the best choice once your marketplace is busy. They are built for automatic emails, have generous limits and show you what was delivered.
• Your business mailbox (Google Workspace, Zoho Mail, Microsoft 365, your domain host) is fine for a small site. These services limit how many emails you can send per day, often a few hundred to a couple of thousand, and stop sending when you reach it.
• A free address (@gmail.com, @outlook.com, @yahoo.com) is the worst choice: low limits, and emails “from” a free address sent by a website often end up in spam. Use an address on your own domain instead. See Email addresses on your domain.

Set up SMTP

1. Get the SMTP details from your provider: host, port, security type, user name and password.
2. In the admin panel, open Email in the sidebar.
3. Under Email Service, choose SMTP.
4. Fill in the fields (see the table below).
5. Under Addresses, set Notify Email to the address you send from. With most providers it must be the mailbox you sign in with, or an address verified with them.
6. Click Save changes.

Yclas sends a test email to your Notify Email straight away and tells you whether it worked. Use Send a test email at the top of the page to try again after a change.

Setting	What to enter
SMTP Host	The server name, for example smtp.zoho.com.
SMTP Port	Usually 587 (with TLS) or 465 (with SSL).
SMTP Secure	TLS for port 587, SSL for port 465, None only if your provider says so.
SMTP Auth	Enabled for almost every provider: the server needs your user name and password.
SMTP User	Usually your full email address, or the user name your provider gives you.
SMTP Password	Your password, or an app password or SMTP key (see below).

Port 465 always goes with SSL and port 587 with TLS. Mixing them up is the most common reason the test email fails.

Settings for common providers

Check your provider’s own help pages too, as they sometimes change.

Provider	Host	Port and security	User and password
Google Workspace or Gmail	smtp.gmail.com	465 SSL or 587 TLS	Your full address, and an app password (your normal password won’t work).
Zoho Mail	smtp.zoho.com (smtp.zoho.eu for EU accounts)	465 SSL or 587 TLS	Your full address and password, or an app-specific password if you use two-factor sign-in.
Microsoft 365 or Outlook	smtp.office365.com	587 TLS	Your full address and password. SMTP sign-in must be allowed for the mailbox.
Amazon SES	email-smtp.<region>.amazonaws.com	587 TLS	The SMTP credentials you create in the SES console (not your AWS password).
Brevo	smtp-relay.brevo.com	587 TLS	Your Brevo login and an SMTP key.
SendGrid	smtp.sendgrid.net	587 TLS	The word apikey as the user, and an API key as the password.
Mailgun	smtp.mailgun.org (smtp.eu.mailgun.org for EU domains)	587 TLS	The SMTP login and password of your Mailgun domain. Or use the Mailgun integration.

Google needs 2-Step Verification turned on before it lets you create an app password. Microsoft is gradually turning off password sign-in for SMTP; if Microsoft 365 refuses your details, use an email-sending service instead.

When sending fails

If the test email fails, or you see “Email not sent. Please set up the SMTP settings.” in the admin panel:

• Check host, port and security together. 465 with SSL, 587 with TLS.
• Check the password. Gmail and Zoho with two-factor sign-in need an app password. Copy it without spaces.
• Check the sender. Your Notify Email must be an address the server lets you send from, usually the same one as SMTP User.
• Check your provider’s limits. A mailbox that has hit its daily limit refuses emails until the next day.
• Look at your provider’s dashboard. Many providers block a first sign-in from a new server and ask you to confirm it was you.

Members still not getting emails that were sent? See Make sure your emails arrive and Emails aren’t arriving.

Related guides

• Email settings — sender name, addresses and the other sending services.
• Make sure your emails arrive — SPF, DKIM and DMARC.
• Mailgun and Elastic Email — send through their API instead of SMTP.