The SendGrid SMTP settings are: server smtp.sendgrid.net, port 587 with TLS, the word apikey as the username, and your SendGrid API key as the password. SendGrid also accepts ports 25 and 2525, plus 465 with SSL. You must verify a sender identity before SendGrid will send your mail.
| Setting | Value | Notes |
|---|---|---|
| SMTP server | smtp.sendgrid.net | Use the name, not an IP address |
| Port and security | 587 with TLS (STARTTLS) | SendGrid's advice if you are unsure |
| Other ports | 2525 or 25 with TLS; 465 with SSL | Port 25 is often blocked by hosts |
| Username | apikey | Type that exact word |
| Password | Your SendGrid API key | Needs "Mail Send" permission |
| Incoming IMAP / POP | Not offered | SendGrid only sends mail |
Before you add it to your site, test these SendGrid SMTP settings in the free SMTP Tester. It checks the connection and the security certificate without a password. If you enter apikey and your key, it can send one test message.
What is SendGrid SMTP, in plain words?
SMTP is the way email gets sent. SendGrid runs an SMTP relay: a sending service your website or app hands messages to. It suits mail your site sends by itself, such as sign-up emails, receipts and form alerts. SendGrid is not a mailbox, so there is no IMAP or POP for reading mail.
A port is a numbered door on the server. TLS on port 587 means the line starts plain and then switches on encryption (also called STARTTLS). SSL on port 465 locks the line from the start. An API key is a long secret code that works like a password for apps.
What do I need before I start?
- An API key with Mail Send permission. Create it in your SendGrid account. Copy it once and keep it safe.
- A verified sender identity. This is the From address people see. SendGrid offers two ways. Single Sender Verification checks one address, and SendGrid says it is for testing. Domain authentication checks your whole domain through DNS records. SendGrid recommends it before real sending, and then you can send from any address on that domain.
- Access to your domain's DNS if you choose domain authentication.
How do I use the SendGrid SMTP settings in WordPress?
WP Mail SMTP has its own SendGrid mailer that only needs the API key. If you prefer plain SMTP, or use another plugin, choose Other SMTP:
- Install and activate WP Mail SMTP, then open its settings.
- Set From Email to an address on your verified domain, or your verified single sender. Tick Force From Email.
- Choose Other SMTP as the mailer.
- Enter
smtp.sendgrid.netas the SMTP Host. - Pick TLS and port 587.
- Turn on Authentication. Type
apikeyas the username and paste your API key as the password. - Save and send a test email from the Tools tab.
FluentSMTP and Post SMTP use the same values. Paste the key with care: SendGrid warns that a hidden line break or space breaks the login.
Can I use SendGrid in an email app or on my phone?
Only for sending, and few people do. SendGrid has no inbox, so you cannot read mail with it. Keep your normal mailbox, such as Microsoft 365 or Gmail, for daily email. Use SendGrid for the mail your website or app sends on its own.
Does SendGrid have SMTP limits?
SendGrid's SMTP guide lists two connection limits. You may send up to 5,000 messages per SMTP connection. You may open up to 10,000 connections at the same time from one server. A normal WordPress site will never come close.
What do common SendGrid SMTP errors mean?
- 535 authentication failed: the username is not the word
apikey, or the key is wrong. Do not use your SendGrid login name. Check for a space or line break at the end of the key. - Login works but mail is refused: the From address is not a verified sender identity. Verify it, or authenticate the domain.
- A new key fails to log in: check that the key has Mail Send permission. If not, make a new key with that permission.
- Timeout: your web host blocks the port. Port 25 is the one most often blocked. Try 587 first, then 2525 or 465.
- Mail blocked with no clear reason: the message may have no From header. SendGrid blocks mail without one, so make sure your plugin or code sets a From address.
- It worked, then stopped: check that you typed
smtp.sendgrid.netand not an IP address. SendGrid says its IP addresses can change without notice.
Why do my emails land in spam?
SendGrid gets the mail out. Inboxes still check your domain, so set up domain authentication in SendGrid. It asks you to add a few records to your DNS. Three DNS records do most of the work. SPF lists the servers that may send for your domain. DKIM adds a digital signature to each message. DMARC tells inboxes what to do when those checks fail.
Start with our guide what is an SPF record. Then run your domain through the DNS and Email Checker to see which records are missing.
The SendGrid SMTP settings rarely change: smtp.sendgrid.net, port 587 with TLS, the word apikey, and an API key with Mail Send permission. Verify your sender, then run a quick check in the SMTP Tester. For other services, see our SMTP settings list.
Frequently asked questions
What is the SendGrid SMTP username?
It is the exact word apikey, in lower case. It is not your SendGrid login name and not the key itself. The API key goes in the password field.
Which port should I use for SendGrid?
SendGrid suggests port 587 with TLS if you are not sure. It also accepts 25 and 2525 with TLS, and 465 with SSL. Many web hosts block port 25, so 2525 is a good second choice.
Why does SendGrid not send my emails after I log in?
The most common reason is an unverified From address. SendGrid needs a verified sender identity, either one single sender or an authenticated domain. Verify one, then send your test again.
