WP Mail SMTP
Widely used SMTP plugin from the WPForms team: 15 mailers free, with logs, alerts, backup connections and smart routing in Pro.
96
Solid Mail
Free SMTP plugin from SolidWP (formerly WP SMTP, now moving to Kadence) with provider presets, From-based routing, fallback and an email log.
Free installs60K+WordPress.org, active
Rating4.2/552 reviews
Price fromFreeFree
Last updated12 May 2026Version 3.0.0
Overview
Solid Mail is the 2024 relaunch of the long-running WP SMTP plugin, first released in 2012. SolidWP, part of StellarWP/Liquid Web, took it over, and version 3.0 began rebranding it under Kadence, with documentation now hosted by Nexcess, where it is being renamed Kadence Mail. It is still listed on WordPress.org under the wp-smtp slug and is completely free.
The plugin hands WordPress email to an external email provider instead of PHP mail. You add connections using presets for SendGrid, Mailgun, Brevo, Amazon SES and Postmark, or a manual SMTP connection for any other host. Most presets fill in the provider’s SMTP relay settings rather than calling its HTTP API. Since version 2.2 you can keep several connections active at once. Each handles mail from a particular From address, so WooCommerce receipts could go through one provider and account emails through another.
Fallback and logging
- A Default connection catches emails whose From address matches no other connection.
- If a send fails, Solid Mail retries it through the default or other active connections.
- The Mail Log shows sender, recipient, subject, time and SMTP errors, with a full message preview.
- Search, delete selected entries, clear all logs or export a date range to CSV.
- An Email Test tab sends a test message through a chosen connection.
Limitations
The feature set is basic next to modern rivals. There is no Gmail or Microsoft 365 OAuth (Gmail and Outlook need app passwords via manual SMTP), no resend button, no failure alerts, no delivery charts and no automatic log retention. There is also no staging mode, no option to force a single From address on every email and no WP-CLI. Credentials are stored in the database without encryption, and support is limited to the WordPress.org forum. Reviews mention a PHP 8.4 crash in 2025 and some spam issues after updates, and the ownership changes add uncertainty about its long-term direction.
Who should pick it: sites already on WP SMTP, or users who want a light, free plugin that routes different From addresses through different SMTP providers with a simple log. Anyone who needs OAuth, alerts or resend should look elsewhere.
Best for: Existing WP SMTP users or simple sites that want free From-address routing across SMTP providers.
Solid Mail covers the basics: provider presets, multiple From-based connections, a fallback and a usable log, all free. It lacks OAuth, resend, alerts and credential encryption, and the move from SolidWP to Kadence makes its future less clear, so most new sites will find better-equipped free options.
Pros
- Free, with presets for SendGrid, Mailgun, Brevo, Amazon SES and Postmark
- Several active connections, each matched to a From address
- Default connection fallback and retry through other connections on failure
- Mail log with SMTP errors, message preview and CSV export
- Long history (since 2012) and a lightweight footprint
Cons
- No Gmail or Microsoft 365 OAuth sign-in
- No resend, failure alerts or delivery reports
- Credentials stored unencrypted, with no wp-config.php option in the current version
- Several ownership and brand changes (WP SMTP to Solid Mail to Kadence Mail)
- Forum-only support and some negative reviews after updates
Key features
What Solid Mail highlights on its WordPress.org page and its own website, split by version.
Free version WordPress.org
- SendGrid, Mailgun, Brevo presets
- Amazon SES and Postmark connections
- Manual SMTP for any provider
- Multiple active connections
- Routing by From address
- Default connection fallback
- Retry via alternative connections
- Mail log with SMTP errors
- Full message preview in log
- CSV export by date range
- Bulk delete and clear logs
- Built-in test email tab
Feature checklist
12 of 23 features we track in SMTP & Email Delivery, feature score 40/100
Sending & mailers 5/8
Any SMTP server Key
Send through any SMTP host with your own credentials.
Manual SMTP connection for any host with port, encryption and authentication.
Included
API mailer integrations Key
Native API connections to SendGrid, Mailgun, Brevo, Postmark and similar.
Presets for SendGrid, Mailgun, Brevo and Postmark; most connect via the provider's SMTP relay, not its API.
Partial
Gmail & Google Workspace Key
Sign in with Google (OAuth) instead of storing a password.
No Google OAuth; Gmail works only through manual SMTP with an app password.
Not included
Microsoft 365 / Outlook
Send through Outlook or Microsoft 365 with OAuth.
No Microsoft OAuth; Outlook/365 only via manual SMTP settings.
Not included
Amazon SES
Native Amazon SES integration.
SES preset uses SES SMTP credentials and endpoint rather than the SES API.
Partial
Backup connection Key
Falls back to a second mailer if the main one fails.
Default connection plus 'Use Alternative Connections on Failure' retries via other connections.
Included
Smart routing
Send different emails through different connections by rules.
Each connection handles emails from its own From address; no other rule types.
Partial
Setup wizard
Guided setup with a test email at the end.
Per-provider setup forms but no guided wizard; test email is a separate tab.
Not included
Logs & monitoring 3/7
Email log Key
Keeps a record of every email sent from the site.
Mail Log records sender, recipient, subject, time and SMTP errors.
Included
Resend from the log
Resend failed or individual emails from the log.
No resend option in the log.
Not included
Open & click tracking
See whether emails were opened and links clicked.
No open or click tracking.
Not included
Failure alerts Key
Alerts by email, Slack, SMS or push when sending fails.
No email or chat alerts when sending fails.
Not included
Automatic retry & queue
Queues emails and retries failed sends automatically.
Failed sends are retried immediately through another connection; no queue or delayed retries.
Partial
Delivery reports
Charts or weekly summaries of sent and failed emails.
No charts or summary reports.
Not included
Log retention & attachments
Control how long logs are kept, with optional attachment storage.
Logging can be turned off and logs deleted or exported; no automatic retention period.
Partial
Email control 2/4
Force from name & address
Override the sender name and address on every email.
Each connection stores a From name and email, but there is no option to force one sender on all emails.
Partial
Turn WordPress emails on or off
Disable individual core, update or WooCommerce notification emails.
No options to disable individual WordPress or WooCommerce emails.
Not included
Stop sending / test mode
Block outgoing email on staging sites or while testing.
No option to block or simulate outgoing email.
Not included
Test email & diagnostics
Send a test email and see a readable error if it fails.
Email Test tab sends a test through a chosen connection and records errors.
Included
Security & admin 2/4
Secure credential storage
Store keys in wp-config constants or encrypted in the database.
Credentials are kept in the database without encryption; wp-config support was legacy (v1.1.10).
Not included
Multisite support
Network-wide or per-site settings on multisite.
Multisite support is not documented.
Not verified
No paywalled mailers
All supported mailers are available in the free version.
Free plugin with no paid edition; all providers included.
Included
Developer hooks & WP-CLI
Hooks, filters or WP-CLI commands for developers.
REST endpoints for connections and a few filters; no documented hooks or WP-CLI.
Partial
Pricing
Free
$0On WordPress.org
Free
Freeper yearUnlimited
Free on WordPress.org; no paid version. Support via the WordPress.org forum.
Prices are list prices from the vendor's site, checked 14 Oct 2026. Many vendors discount the first year.
How many sites use Solid Mail?
Free installs from WordPress.org, the vendor's own claim, and our estimate of paid installs.
Free version (WordPress.org)
60K+
Active installations reported by WordPress.org.
Vendor claim
—
The vendor does not publish a total.
Estimated Pro / paid installs
n/a
There is no paid version.
Stats & health
Weekly downloads
1,363 downloads last week, 1.2M all time
Rating breakdown
| Version | 3.0.0 |
|---|---|
| Last updated | 12 May 2026 (175 days ago) |
| Tested up to | WordPress 6.9.11 |
| Requires | WordPress 6.4+, PHP 7.4+ |
| Support threads (2 months) | 0 of 1 resolved |
| On WordPress.org since | 10 Nov 2012 |
Company & policy
| Founded | 2012 (source, 11 Oct 2026) First released as WP SMTP (1.1.2) in Nov 2012; relaunched as Solid Mail 2.0 in Sep 2024. |
|---|
Solid Mail compared
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FAQ
Is Solid Mail free?
Yes. Solid Mail has a free version on WordPress.org.
How many sites use Solid Mail?
WordPress.org reports 60K+ active installations of the free version.
Does Solid Mail have any smtp server?
Yes: included. Manual SMTP connection for any host with port, encryption and authentication.
Does Solid Mail have api mailer integrations?
Yes: partial. Presets for SendGrid, Mailgun, Brevo and Postmark; most connect via the provider's SMTP relay, not its API.
Does Solid Mail have gmail & google workspace?
No: not included. No Google OAuth; Gmail works only through manual SMTP with an app password.
Does Solid Mail have backup connection?
Yes: included. Default connection plus 'Use Alternative Connections on Failure' retries via other connections.
Does Solid Mail have email log?
Yes: included. Mail Log records sender, recipient, subject, time and SMTP errors.
Does Solid Mail have failure alerts?
No: not included. No email or chat alerts when sending fails.
Is Solid Mail the same plugin as WP SMTP?
Yes. WP SMTP was relaunched as Solid Mail in version 2.0 (2024) and keeps the wp-smtp slug on WordPress.org. Version 3.0 started rebranding it under Kadence, with Nexcess docs calling it Kadence Mail.
Is there a paid version?
No. The plugin is free and supported through the WordPress.org forum.
Can I send WooCommerce emails through a different provider?
Yes. Add a connection for the store's From address and another for other emails; each email uses the connection that matches its From address.
Does Solid Mail support Gmail sign-in?
Not with OAuth. You can use a manual SMTP connection to Gmail with an app password.
What happens if a connection fails?
With alternative connections enabled, the email is retried through the default connection or other active connections, trying those that match the same From address first.
Last updated 11 Oct 2026. Spotted something wrong? Suggest an edit.