At a glance
MC4WP: Mailchimp for WordPress
The #1 Mailchimp plugin for WordPress. Allows you to add a multitude of newsletter sign-up methods to your site.
Post SMTP – Complete Email Deliverability and SMTP Solution with Email Logs, Alerts, Backup SMTP & Mobile App
Improve WordPress email deliverability. Connect Gmail SMTP, Microsoft 365, Brevo, SendGrid, Mailgun, Zoho, Amazon SES, etc. #1 WordPress SMTP Plugin.
Full Comparison
Technical Specs
| Metric | MC4WP | Post SMTP |
|---|---|---|
| Requires WP | 5.3+ | 5.6.0+ |
| Requires PHP | 7.4+ | 7.0+ |
| Tested up to WP | 7.0 | 7.0 |
| Plugin age | 13 yrs | 9 yrs |
Quick Verdict
MC4WP wins this comparison. It is the best Mailchimp plugin for WordPress, with 1.0M+ active installs and a 4.8/5 rating from 1496 reviewers. Post SMTP is a strong choice for fixing email deliverability, but MC4WP serves a larger audience. If your main goal is to integrate Mailchimp in WordPress, choose MC4WP. If your site has transactional email problems, choose Post SMTP.
Feature Comparison: MC4WP vs Post SMTP
| Feature | MC4WP | Post SMTP |
|---|---|---|
| Primary purpose | Mailchimp newsletter sign-up forms | SMTP email deliverability and logs |
| Mailchimp integration | Native, built for Mailchimp API | Not designed for Mailchimp |
| Email logging | Not available | Built-in email log viewer |
| SMTP providers supported | Not applicable | Gmail, Microsoft 365, Brevo, SendGrid, Mailgun, Zoho, Amazon SES |
| Form types | Checkbox, pop-up, widget, shortcode, comment form, WooCommerce | Not applicable |
| Double opt-in support | Yes, configurable | Not applicable |
| Alert system | Not available | Email failure alerts and backup SMTP |
| Mobile app | Not available | Companion mobile app for monitoring |
Who Should Use MC4WP
- Site owners who want to add a Mailchimp form to WordPress quickly. The plugin has 1.0M+ active installs, making it the most trusted solution for this task.
- E-commerce stores using WooCommerce that need a Mailchimp form for WooCommerce. You can add sign-up checkboxes directly on checkout and registration pages.
- Marketers who rely on double opt-in compliance. MC4WP offers a Mailchimp double opt-in WordPress setting that syncs seamlessly with your Mailchimp audience settings.
Who Should Use Post SMTP
- Users who need to fix WordPress emails not sending. Post SMTP resolves deliverability issues by routing mail through a proper SMTP server, trusted by 300K+ sites.
- Developers who want to connect Gmail SMTP to WordPress. The plugin supports Gmail, Microsoft 365, and seven other providers out of the box.
- Teams that require email failure alerts. Post SMTP sends notifications when an email fails, and it offers a backup SMTP server to keep your site running when the primary server goes down.
Community & Support
Post SMTP shows a support resolution rate of 83% (15 of 18 threads resolved in 2 months). The plugin's rating distribution shows 91% five-star reviews and 6% one-star reviews. MC4WP has a higher five-star rating share at 92% and a lower one-star share at 3%, though its support sample is too small to draw conclusions from thread data. Both plugins maintain strong user satisfaction, with MC4WP holding a slight edge in raw approval.
Verdict: MC4WP or Post SMTP for WordPress sites?
Pick MC4WP if you are looking for the best Mailchimp plugin for WordPress. It has 1.0M+ installs, a 4.8/5 rating, and 92% five-star reviews. It handles everything from pop-up forms to WooCommerce integration.
Pick Post SMTP if your priority is WordPress email deliverability. Its 83% support resolution rate and built-in email logs make it the best SMTP plugin for WordPress when your transactional emails are failing. The two plugins solve different problems. For newsletter growth, MC4WP is the clear winner. For email sending reliability, Post SMTP is the right tool.
This comparison is AI-generated from live WordPress.org data. Install counts, ratings, versions and support statistics sync weekly, so the numbers on this page stay current. Content passes automated quality checks before publishing, and pages below our quality threshold are held for human review.
Read our full methodologyFrequently Asked Questions
Q How many people use MC4WP compared to Post SMTP?
MC4WP has 1.0M+ active installs while Post SMTP has 300K+, meaning MC4WP is used on more sites.
Q Which has better user ratings — MC4WP or Post SMTP?
MC4WP averages 4.8/5 from 1,496 reviews, while Post SMTP averages 4.7/5 from 523 reviews — MC4WP has the higher average rating.
Q Which is more actively maintained — MC4WP or Post SMTP?
MC4WP was last updated on Jun 4, 2026 and Post SMTP on Jun 3, 2026, so MC4WP received the more recent update.
Q Are MC4WP and Post SMTP both free?
Yes — both MC4WP and Post SMTP are free to install from the official WordPress.org plugin directory. Some features may require a paid upgrade offered by the plugin author.
Q Is MC4WP or Post SMTP better for WordPress sites?
MC4WP is better if you need to build email lists and sync subscribers with Mailchimp, while Post SMTP is better if your main problem is getting your site's emails delivered to inboxes. They solve completely different problems, so the right choice depends on whether you need to grow an audience or fix email delivery.
Q Which is easier to set up for a WordPress beginner — MC4WP or Post SMTP?
MC4WP is easier for a beginner because you just connect your Mailchimp account and drop a form widget onto your site. Post SMTP requires configuring SMTP credentials from your email provider, which can be more technical if you are not familiar with server settings.
Q What is the biggest feature difference between MC4WP and Post SMTP?
MC4WP focuses entirely on Mailchimp integration, letting you create sign-up forms, popups, and WooCommerce checkout checkboxes. Post SMTP focuses on email delivery, logging, and troubleshooting, with support for Gmail SMTP and Office 365. One builds your list, the other makes sure your emails actually arrive.
Q Can you switch from MC4WP to Post SMTP (or the other way) without losing data?
Yes, you can switch without losing data because the plugins do not overlap in function. MC4WP stores your Mailchimp subscriber data in Mailchimp's servers, not in WordPress, and Post SMTP handles email logs and delivery settings. Uninstalling one will not affect the other's data.
Q Which type of site should choose MC4WP, and which should choose Post SMTP?
Choose MC4WP if you run a blog, online store, or membership site that needs to collect email subscribers and send them to Mailchimp. Choose Post SMTP if your site relies on transactional emails like password resets, order confirmations, or contact form notifications and those emails are not being delivered.