diff --git a/en_US/upgrade/0-upgrade.iredmail.1.4.2-1.4.3.md b/en_US/upgrade/0-upgrade.iredmail.1.4.2-1.4.3.md
index bc5dbfdc..375bb3a3 100644
--- a/en_US/upgrade/0-upgrade.iredmail.1.4.2-1.4.3.md
+++ b/en_US/upgrade/0-upgrade.iredmail.1.4.2-1.4.3.md
@@ -41,6 +41,7 @@ so that you can know which version of iRedMail you're running. For example:
   available on:
     - CentOS 7 and later
     - Debian 10 and later
+    - Ubuntu 18.04 and later
     - FreeBSD
     - OpenBSD
 - Greatly improve the performance of http keep-alive connections over SSL by
@@ -51,6 +52,7 @@ so that you can know which version of iRedMail you're running. For example:
   available on:
     - CentOS 7 and later
     - Debian 9 and later
+    - Ubuntu 18.04 and later
     - FreeBSD
     - OpenBSD
 - Remove weak ssl cipher: `AES256+EDH`.
diff --git a/html/upgrade.iredmail.1.4.2-1.4.3.html b/html/upgrade.iredmail.1.4.2-1.4.3.html
index a0468513..b224d689 100644
--- a/html/upgrade.iredmail.1.4.2-1.4.3.html
+++ b/html/upgrade.iredmail.1.4.2-1.4.3.html
@@ -64,6 +64,7 @@ contributions. See also:
   available on:<ul>
 <li>CentOS 7 and later</li>
 <li>Debian 10 and later</li>
+<li>Ubuntu 18.04 and later</li>
 <li>FreeBSD</li>
 <li>OpenBSD</li>
 </ul>
@@ -78,6 +79,7 @@ contributions. See also:
   available on:<ul>
 <li>CentOS 7 and later</li>
 <li>Debian 9 and later</li>
+<li>Ubuntu 18.04 and later</li>
 <li>FreeBSD</li>
 <li>OpenBSD</li>
 </ul>