diff --git a/Library/Homebrew/brew.sh b/Library/Homebrew/brew.sh
index c7bc840e7d..719bee9e86 100644
--- a/Library/Homebrew/brew.sh
+++ b/Library/Homebrew/brew.sh
@@ -247,7 +247,7 @@ update-preinstall() {
   [[ -z "$HOMEBREW_NO_AUTO_UPDATE" ]] || return
   [[ -z "$HOMEBREW_UPDATE_PREINSTALL" ]] || return
 
-  if [[ "$HOMEBREW_COMMAND" = "install" || "$HOMEBREW_COMMAND" = "upgrade" ]]
+  if [[ "$HOMEBREW_COMMAND" = "install" || "$HOMEBREW_COMMAND" = "upgrade" || "$HOMEBREW_COMMAND" = "tap" ]]
   then
     brew update --preinstall
   fi
diff --git a/Library/Homebrew/manpages/brew.1.md.erb b/Library/Homebrew/manpages/brew.1.md.erb
index 7bdcc7b921..60557173de 100644
--- a/Library/Homebrew/manpages/brew.1.md.erb
+++ b/Library/Homebrew/manpages/brew.1.md.erb
@@ -182,8 +182,8 @@ can take several different forms:
     If set, Homebrew will not send analytics. See: <https://github.com/Homebrew/brew/blob/master/share/doc/homebrew/Analytics.md#analytics>
 
   * `HOMEBREW_NO_AUTO_UPDATE`:
-    If set, Homebrew will not auto-update before running `brew install` and
-    `brew upgrade`.
+    If set, Homebrew will not auto-update before running `brew install`,
+    `brew upgrade` or `brew tap`.
 
   * `HOMEBREW_NO_EMOJI`:
     If set, Homebrew will not print the `HOMEBREW_INSTALL_BADGE` on a
diff --git a/share/doc/homebrew/brew.1.html b/share/doc/homebrew/brew.1.html
index 8e46682ff3..d768844b5b 100644
--- a/share/doc/homebrew/brew.1.html
+++ b/share/doc/homebrew/brew.1.html
@@ -579,8 +579,8 @@ the number of parallel jobs to run when building with <code>make</code>(1).</p>
 
 <p><em>Default:</em> the number of available CPU cores.</p></dd>
 <dt><code>HOMEBREW_NO_ANALYTICS</code></dt><dd><p>If set, Homebrew will not send analytics. See: <a href="https://github.com/Homebrew/brew/blob/master/share/doc/homebrew/Analytics.md#analytics" data-bare-link="true">https://github.com/Homebrew/brew/blob/master/share/doc/homebrew/Analytics.md#analytics</a></p></dd>
-<dt><code>HOMEBREW_NO_AUTO_UPDATE</code></dt><dd><p>If set, Homebrew will not auto-update before running <code>brew install</code> and
-<code>brew upgrade</code>.</p></dd>
+<dt><code>HOMEBREW_NO_AUTO_UPDATE</code></dt><dd><p>If set, Homebrew will not auto-update before running <code>brew install</code>,
+<code>brew upgrade</code> or <code>brew tap</code>.</p></dd>
 <dt><code>HOMEBREW_NO_EMOJI</code></dt><dd><p>If set, Homebrew will not print the <code>HOMEBREW_INSTALL_BADGE</code> on a
 successful build.</p>
 
diff --git a/share/man/man1/brew.1 b/share/man/man1/brew.1
index 7bc65da91f..258bbff577 100644
--- a/share/man/man1/brew.1
+++ b/share/man/man1/brew.1
@@ -804,7 +804,7 @@ If set, Homebrew will not send analytics\. See: \fIhttps://github\.com/Homebrew/
 .
 .TP
 \fBHOMEBREW_NO_AUTO_UPDATE\fR
-If set, Homebrew will not auto\-update before running \fBbrew install\fR and \fBbrew upgrade\fR\.
+If set, Homebrew will not auto\-update before running \fBbrew install\fR, \fBbrew upgrade\fR or \fBbrew tap\fR\.
 .
 .TP
 \fBHOMEBREW_NO_EMOJI\fR