WordPress Contact Form Not Sending Emails? Why It Happens and How to Fix It

A visitor fills in your contact form, presses Send and sees a green "Thank you, your message has been sent." You never get the email. You find out weeks later, when a customer rings to ask why nobody replied.

This is one of the most common WordPress problems we fix, and one of the most expensive, because every lost message is a lost enquiry. The good news: the cause is nearly always the same, and the fix takes under an hour. This guide shows why it happens, with screenshots from a test site, and the setup we use on client sites so form emails actually arrive.

"Sent" is not the same as delivered

We set up a fresh WordPress test site with Contact Form 7, one of the most used form plugins, and filled in the form. This test site has no working mail setup at all, so no email went anywhere. The form still reported success:

That is why this problem goes unnoticed for so long. Nothing on the website looks broken. The email is either never sent by the server, rejected by the receiving mail provider, or quietly filed in spam.

Why WordPress emails go missing

Out of the box, WordPress sends email using PHP's built-in mail function on your web server. That works, technically, but receiving providers like Gmail and Outlook see a message that:

• comes from a web server, not a mail server. On shared hosting, that server's address is shared with hundreds of other sites, some of which send spam.
• cannot prove it is allowed to send for your domain. Google's sender guidelines ask every sender to authenticate with SPF or DKIM. Plain server mail usually has neither for your domain.
• often uses a From address the server does not own. Some forms are set to send "from" the visitor's Gmail address. To Gmail, that looks exactly like a forged email.

Some hosts go further and block or limit PHP mail entirely to stop spam. In that case nothing leaves the server at all.

Quick checks before you change anything

1. Check spam and every other folder of the inbox the form sends to, including Gmail's Promotions and Updates tabs.
2. Check where the form sends to. In Contact Form 7, open the form and the Mail tab. Make sure the "To" address is right and still in use. Other form plugins have a similar "Notifications" setting.
3. Check the From address. It should be an address on your own domain, like website@yourdomain.com. If it is set to the visitor's email, move that to a Reply-To: line in the additional headers so you can still reply with one click.
4. Check WordPress's own emails. Use "Lost your password?" on the login page. If that email does not arrive either, the problem is the whole site's email, not the form.

The fix: send through SMTP

SMTP means WordPress logs in to a real mail service and sends through it, instead of using the web server. The receiving side then sees a properly authenticated email from a sender it trusts. The easiest way to set it up is a free SMTP plugin. We have set up every plugin in the table below on client websites, and there is no single best one. The right pick depends mostly on which email service the client uses.

The popular SMTP plugins

Plugin	Free version	Paid only	Best for
WP Mail SMTP	Google / Gmail, Brevo, Mailgun, Postmark, SendGrid, SMTP2GO, Other SMTP and more	Microsoft 365 / Outlook, Zoho Mail, Amazon SES, email log	Google Workspace or a sending service. The most installed, with an easy setup wizard.
FluentSMTP	Everything: Microsoft 365 / Outlook, Google / Gmail, Amazon SES, Brevo, Mailgun, Postmark, SendGrid, Zoho (SMTP), any SMTP server, email log, fallback connection	Nothing. There is no Pro version.	Microsoft 365, and anyone who wants every feature free.
Post SMTP	Google / Gmail, Brevo, Mailgun, Postmark, SendGrid, Other SMTP, email log, failure alerts	Microsoft 365 / Outlook, Zoho Mail, Amazon SES	Logs and alerts (email, Slack, mobile app) when a message fails.
WPO365 Microsoft 365 Graph Mailer	Sends through Microsoft 365, Outlook.com or Hotmail using Microsoft Graph, Microsoft's own API	Failure alerts, email log, auto-retry, shared mailbox, send as another user	Microsoft 365 only. Built for it and nothing else.
Zoho Mail for WordPress	Sends through your Zoho Mail account using Zoho's own API	Nothing	Zoho Mail users. It is the official plugin from Zoho, and sent emails show up in your Zoho Sent folder.
SureMail	Everything: Amazon SES, Google / Gmail, Brevo, Mailgun, Postmark, SendGrid, Other SMTP, email log, fallback connections, retries, alerts	Nothing. It is fully free.	Sending services and Google Workspace. It has no Microsoft 365 option.
Easy WP SMTP	SendLayer, Brevo, Mailgun, Postmark, SendGrid, SMTP2GO, Other SMTP and more	Microsoft 365 / Outlook, Google / Gmail, Zoho Mail, Amazon SES, email log, alerts, backup connection	Sending services. From the same company as WP Mail SMTP.
Solid Mail	SendGrid, Mailgun, Brevo, Amazon SES, Postmark, any SMTP server, email log, fallback connection	Nothing	Sending services. Made by SolidWP, the team behind Solid Security.
Email Deliverability (Site Mailer)	Sends through Elementor's own email service, with a 30-day email log and resend	Needs an Elementor account	Elementor users who do not want to set up a mail service at all. It does not use your own mailbox.

So WP Mail SMTP is the best known, but its free version is one of the most limited if you are on Microsoft 365 or Zoho. For those, FluentSMTP, WPO365 or Zoho's own plugin does the job for free. If you use a sending service such as Amazon SES, FluentSMTP and SureMail include it free.

Which mailer to choose

Whichever plugin you install, it asks you to pick a mailer. This is the WP Mail SMTP screen. The other plugins have a similar list:

You use	Pick	Notes
Google Workspace	Google / Gmail in any of the plugins	Sends through your own Workspace account.
Microsoft 365	Outlook / Microsoft 365 in FluentSMTP, or WPO365	Free in both. Paid in WP Mail SMTP, Post SMTP and Easy WP SMTP. Needs an app registered in Microsoft Azure (see below).
Zoho Mail	Zoho Mail for WordPress	Free and official. FluentSMTP's Zoho SMTP connection works too.
Email from your host (cPanel and similar)	Other SMTP	Use the mailbox's SMTP server, port, username and password from your host.
A busy site or a store	Brevo, Mailgun, Postmark, SendGrid and similar	Built for sending website email. Several offer a free tier for low volumes.

Set the From address to one on your domain, and turn on the option that forces it (WP Mail SMTP calls it Force From Email), so every plugin sends from the same trusted address. Then send a test email from the plugin's own test screen, and submit your real contact form once yourself.

Microsoft 365: put the secret's expiry date in your calendar

Microsoft has switched off the old way of sending with just an email address and password, so "Other SMTP" with your Outlook login usually fails. Instead, you register an app in the Microsoft Azure portal (Microsoft Entra ID) and paste its Client ID and Client Secret into the SMTP plugin. That secret does not last forever. Microsoft caps it at 24 months and recommends less than 12, and you choose the expiry when you create it.

When the secret expires, Microsoft stops accepting the connection, and your form emails stop with it. Nothing on the website changes. The form still says "sent". It is the same silent failure this post started with, just a year or two later.

1. Note the expiry date shown next to the secret under Certificates & secrets in the Azure app.
2. Add a calendar reminder two to four weeks before that date, with a second alert a few days before, for whoever looks after the website.
3. Before it expires, create a new secret in the same Azure app, paste it into the SMTP plugin, send a test email, then delete the old secret.

Turn on the plugin's failure alerts too, if it has them, so a broken connection reaches you even if the reminder gets missed.

Add SPF, DKIM and DMARC to your domain

These are three short DNS records that tell the world which services may send email for your domain. Your mail service gives you the exact values to copy. You add them wherever your domain's DNS is managed, which is often your domain registrar or host.

• SPF lists the servers allowed to send for your domain. You can only have one SPF record, so add new services to it rather than creating a second one.
• DKIM adds a digital signature to each email that the receiver can check.
• DMARC tells receivers what to do when a message fails those checks. Starting with p=none is fine, it just collects reports.

Google requires SPF or DKIM from everyone sending to Gmail, and all three from bulk senders. A contact form is not bulk mail, but setting up all three is the surest way to keep form emails out of spam.

Keep a copy of every enquiry

Even a perfect setup can fail one day: an expired password, a full mailbox, a DNS change. So it is worth saving every form entry inside WordPress as well. Many form plugins do this built in. For Contact Form 7, the free Flamingo plugin from the same developer stores each submission in the dashboard.

• Form emails send through SMTP, not "Default (none)"
• On Microsoft 365, the Azure secret's expiry date is in the calendar with a reminder
• From address is on your own domain, visitor's email in Reply-To
• SPF, DKIM and DMARC records added for the domain
• Test email and a real form test both arrive in the inbox
• Every submission is also saved in the dashboard
• Somebody tests the form again after any big change to the site

Testing the forms after updates is part of our website maintenance plans, from $10 a month (₹1,500 in India). If your form has gone quiet and you want it sorted, send us your site address. It is worth a phone call too, because this form might be the one that is not reaching us.