WordPress SMTP: 4 Plugins Compared (with Step-by-Step Setup)

If you run WordPress without an SMTP plugin, you are using PHP mail(), which means your transactional email goes out from the shared web host IP, with no DKIM, no SPF alignment, and a near-certainty of landing in spam. Adding a proper SMTP plugin is the single highest-leverage deliverability change a WordPress site can make. The hard part is picking the right plugin.

This article compares the four most-installed SMTP plugins, walks through the setup of each with Target SMTP credentials as the example, and tells you which one fits which type of site. We have no preference between plugins — only between sites.

The Four Plugins

Common Setup Steps

Regardless of plugin, you need three things from your SMTP provider:

• Hostname (e.g. smtp.targetsmtp.it)
• Port (587 for STARTTLS, 465 for implicit TLS)
• Username and password (or API key)

You also need to publish SPF, DKIM and DMARC records for the sending domain before you start. No plugin can fix authentication if DNS is wrong.

Plugin 1: WP Mail SMTP

The most-installed by a wide margin. Owned by Awesome Motive (same group as WPForms). Strong UI, good docs, gentle upsell to pro.

Setup

1. Plugins → Add New → WP Mail SMTP → Install & Activate.
2. Go to WP Mail SMTP → Settings.
3. From Email: noreply@example.com; tick "Force From Email".
4. Mailer: choose "Other SMTP" (or the dedicated Target SMTP integration if available in your version).
5. SMTP Host: smtp.targetsmtp.it; Port: 587; Encryption: TLS.
6. SMTP Authentication: ON; user/password from your Target dashboard.

Best For

Sites where a non-developer admin will configure SMTP. The UI is the friendliest of the four. Logging and email alerting are paywalled.

Plugin 2: Fluent SMTP

Surprise of the last two years. Built by WPManageNinja. Genuinely free, no paywall. Excellent logging UI even on free plan.

Setup

1. Install & activate Fluent SMTP.
2. Settings → Add Connection → Other SMTP.
3. Fill From Name, From Email, Reply-To.
4. SMTP host, port 587, encryption TLS.
5. Username/password.
6. Save and "Send Test".

Best For

Anyone who wants production-grade logging and routing without paying. Multiple connections (e.g. transactional vs marketing on different credentials) work out of the box.

Plugin 3: Post SMTP

Originally Postman SMTP, now Post SMTP. Strong OAuth support (Google, Microsoft). Active Slack/Discord notification for failed sends.

Setup

1. Install & activate Post SMTP.
2. Post SMTP → Show All Settings → Transport.
3. Choose "SMTP" (or OAuth if going via Google/Microsoft).
4. Hostname, port 587, TLS.
5. Authentication: Plain. Username/password.

Best For

Sites that send through Google Workspace or Microsoft 365 (OAuth flow is best-in-class) and sites that want push notifications on send failures.

Plugin 4: Easy WP SMTP

The oldest of the four. Minimal feature set. Some find it the most "stay out of the way" option.

Setup

1. Install & activate Easy WP SMTP.
2. Settings → Easy WP SMTP.
3. From Email, From Name.
4. SMTP Host, Port 587, Encryption TLS.
5. Auth ON, user/password.

Best For

Brochure sites with low send volume where you simply need the contact form to deliver.

The Comparison Matrix

Things That Bite Every Setup

⚠️ Warning: Some hosts (SiteGround, Kinsta, WP Engine) block outbound SMTP from PHP. You must use port 465 (implicit TLS) or use an API-based provider integration instead of raw SMTP.

"Force From Email"

WordPress plugins like WooCommerce often set their own From address (e.g. wordpress@server-hostname.com). Always enable Force From Email or your DKIM alignment breaks.

WooCommerce Customer Notes

WooCommerce uses the same SMTP, but several email templates explicitly bypass the "From" override unless Force is set. Test order confirmations and password resets specifically.

Reply-To vs From

Always set From to a no-reply identity you fully control (and that has SPF/DKIM/DMARC aligned). Set Reply-To to the human address customers should reach. Mixing the two breaks DMARC.

The Test Plan

After setup, test:

1. Plugin built-in test email.
2. Send to a Gmail address; check headers for spf=pass, dkim=pass, dmarc=pass.
3. Send to check-auth@verifier.port25.com; read the auth report.
4. Trigger a real flow (password reset, order confirmation, contact form).
5. Check logs in the plugin for any 4xx/5xx.

Which to Choose

• Small brochure site, single contact form: Easy WP SMTP or Fluent.
• WooCommerce shop with 1k orders/month: Fluent SMTP (free) or WP Mail SMTP Pro.
• Membership / LMS sending courses + transactional: Fluent or Post SMTP.
• Multi-site network: WP Mail SMTP Pro or Fluent.

Closing

The plugin only handles the SMTP handshake. The deliverability comes from the provider behind it. Whichever plugin you pick, point it at a provider that authenticates correctly, suppresses bounced recipients, and gives you observability. Target SMTP supplies all four plugin integrations and shows per-plugin volume and complaint trends in the dashboard, and the Send-Time Firewall can stop a single misconfigured plugin (e.g. forgotten Force From Email) from contaminating the rest of your traffic.