PluginSift

Post SMTP – Complete Email… vs Office 365 User Authentication for… (2026)

Detailed side-by-side comparison of two WordPress plugins, based on real-time data from WordPress.org.

Post SMTP – Complete Email…

Post SMTP – Complete Email…

4.7(518)

400K+ active installs

Free + Premium

Updated 4 days ago
View Post SMTP – Complete Email…
VS
Office 365 User Authentication for…

Office 365 User Authentication for…

5(7)

20 active installs

Free

Updated 6 months ago
View Office 365 User Authentication for…

Quick Verdict

As of April 2026, Office 365 User Authentication for… has a higher user rating (5/5 from 7 reviews) while Post SMTP – Complete Email… leads in active installations (400K+ vs 20). Both are free + premium WordPress plugins. Post SMTP – Complete Email… has accumulated 18M+ total downloads while Office 365 User Authentication for… has 7.5K+.

Detailed Comparison

Rating
4.7/5Post SMTP – Complete Email…
►
Office 365 User Authentication for…5/5
Total Reviews
518Post SMTP – Complete Email…
◄
Office 365 User Authentication for…7
Active Installs
400K+Post SMTP – Complete Email…
◄
Office 365 User Authentication for…20
Total Downloads
18M+Post SMTP – Complete Email…
◄
Office 365 User Authentication for…7.5K+
Support Resolution
76%Post SMTP – Complete Email…
Office 365 User Authentication for…N/A
Last Updated
4 days agoPost SMTP – Complete Email…
◄
Office 365 User Authentication for…6 months ago
First Released
2017Post SMTP – Complete Email…
Office 365 User Authentication for…2018
Age
9 yearsPost SMTP – Complete Email…
Office 365 User Authentication for…8 years
WP Requires
5.6.0+Post SMTP – Complete Email…
Office 365 User Authentication for…3.5.2+
PHP Requires
7.0+Post SMTP – Complete Email…
Office 365 User Authentication for…5.6.36+
Business Model
Free + PremiumPost SMTP – Complete Email…
Office 365 User Authentication for…Free
Latest Version
3.9.1Post SMTP – Complete Email…
Office 365 User Authentication for…2.7

Rating Breakdown

Post SMTP – Complete Email…

4.7/5(518 reviews)
5
91%
4
1%
3
1%
2
1%
1
6%

Office 365 User Authentication for…

5/5(7 reviews)
5
100%
4
0%
3
0%
2
0%
1
0%

Recent Reviews

Post SMTP – Complete Email… Reviews

by frzsombor

Critical and high severity vulnerabilities over and over again

We’ve been using Post SMTP for years. Initially, we started with WP Mail SMTP, but the free version didn’t include logging, while Post SMTP did, and that occasionally came in handy. So we switched to

by jcalmeida

Great Plugin

Great Plugin easy to config and troubleshoot.

by AdamJB13

Great Support for the setup of PostSMTP

Aqib was very helpful in setting up PostSMTP on my site. The plug-in is working very well.

Office 365 User Authentication for… Reviews

No reviews yet

Frequently Asked Questions

Is Post SMTP – Complete Email… or Office 365 User Authentication for… more popular?
Post SMTP – Complete Email… has 400K+ active installations while Office 365 User Authentication for… has 20. Post SMTP – Complete Email… is the more widely-used plugin as of April 2026.
Which has better ratings — Post SMTP – Complete Email… or Office 365 User Authentication for…?
Post SMTP – Complete Email… has a 4.7/5 rating from 518 reviews, while Office 365 User Authentication for… has a 5/5 rating from 7 reviews.
Are Post SMTP – Complete Email… and Office 365 User Authentication for… free?
Post SMTP – Complete Email… is free + premium and Office 365 User Authentication for… is free. Both can be downloaded from the WordPress.org plugin directory.
Which plugin has better support — Post SMTP – Complete Email… or Office 365 User Authentication for…?
Support resolution data is not available for all plugins. Check each plugin's WordPress.org support forum for current response quality.
Which plugin is updated more frequently?
Post SMTP – Complete Email… was last updated 4 days ago and Office 365 User Authentication for… was last updated 6 months ago.

Plugin data sourced from WordPress.org. Comparison and analysis by PluginSift.