diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index c204b20b1..e5fadba68 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -31,6 +31,7 @@ Notable improvements and fixes
 - ``fish_preexec`` and ``fish_postexec`` events are no longer triggered
   for empty commands.
 - The ``test`` builtin now better shows where an error occured (#6030).
+- Add a helper function to know if the user is root (#7031).
 
 Syntax changes and new commands
 -------------------------------
diff --git a/doc_src/cmds/fish_is_root_user.rst b/doc_src/cmds/fish_is_root_user.rst
new file mode 100644
index 000000000..6410525cf
--- /dev/null
+++ b/doc_src/cmds/fish_is_root_user.rst
@@ -0,0 +1,31 @@
+.. _cmd-fg:
+
+fish_is_root_user - check if the current user is root
+=====================================================
+
+Synopsis
+--------
+
+::
+
+    fish_is_root_user
+
+Description
+-----------
+
+``fish_is_root_user`` will check if the current user is root. It can be useful
+for the prompt to display something different if the user is root, for example.
+
+
+Example
+-------
+
+A simple example:
+
+::
+
+    function example --description 'Just an example'
+        if fish_is_root_user
+            do_something_different
+        end
+    end
diff --git a/share/functions/fish_is_root_user.fish b/share/functions/fish_is_root_user.fish
new file mode 100644
index 000000000..812a6a041
--- /dev/null
+++ b/share/functions/fish_is_root_user.fish
@@ -0,0 +1,10 @@
+# To know if the user is root. Used by several prompts to display something
+# else if the user is root.
+
+function fish_is_root_user --description "Check if the user is root"
+    if contains -- $USER root toor Administrator
+        return 0
+    end
+
+    return 1
+end
diff --git a/share/functions/fish_prompt.fish b/share/functions/fish_prompt.fish
index e09191ade..b7dfe3354 100644
--- a/share/functions/fish_prompt.fish
+++ b/share/functions/fish_prompt.fish
@@ -9,7 +9,7 @@ function fish_prompt --description 'Write out the prompt'
     # Color the prompt differently when we're root
     set -l color_cwd $fish_color_cwd
     set -l suffix '>'
-    if contains -- $USER root toor
+    if fish_is_root_user
         if set -q fish_color_cwd_root
             set color_cwd $fish_color_cwd_root
         end
diff --git a/share/tools/web_config/sample_prompts/classic.fish b/share/tools/web_config/sample_prompts/classic.fish
index 6bc71c962..b4d5887c6 100644
--- a/share/tools/web_config/sample_prompts/classic.fish
+++ b/share/tools/web_config/sample_prompts/classic.fish
@@ -2,17 +2,18 @@
 function fish_prompt --description "Write out the prompt"
     set -l color_cwd
     set -l suffix
-    switch "$USER"
-        case root toor
-            if set -q fish_color_cwd_root
-                set color_cwd $fish_color_cwd_root
-            else
-                set color_cwd $fish_color_cwd
-            end
-            set suffix '#'
-        case '*'
+
+    if fish_is_root_user
+        if set -q fish_color_cwd_root
+            set color_cwd $fish_color_cwd_root
+        else
             set color_cwd $fish_color_cwd
-            set suffix '>'
+        end
+
+        set suffix '#'
+    else
+        set color_cwd $fish_color_cwd
+        set suffix '>'
     end
 
     echo -n -s "$USER" @ (prompt_hostname) ' ' (set_color $color_cwd) (prompt_pwd) (set_color normal) "$suffix "
diff --git a/share/tools/web_config/sample_prompts/classic_status.fish b/share/tools/web_config/sample_prompts/classic_status.fish
index 334d17dcc..0a2d50c89 100644
--- a/share/tools/web_config/sample_prompts/classic_status.fish
+++ b/share/tools/web_config/sample_prompts/classic_status.fish
@@ -8,17 +8,18 @@ function fish_prompt --description "Write out the prompt"
 
     set -l color_cwd
     set -l suffix
-    switch "$USER"
-        case root toor
-            if set -q fish_color_cwd_root
-                set color_cwd $fish_color_cwd_root
-            else
-                set color_cwd $fish_color_cwd
-            end
-            set suffix '#'
-        case '*'
+
+    if fish_is_root_user
+        if set -q fish_color_cwd_root
+            set color_cwd $fish_color_cwd_root
+        else
             set color_cwd $fish_color_cwd
-            set suffix '>'
+        end
+
+        set suffix '#'
+    else
+        set color_cwd $fish_color_cwd
+        set suffix '>'
     end
 
     echo -n -s "$USER" @ (prompt_hostname) ' ' (set_color $color_cwd) (prompt_pwd) \
diff --git a/share/tools/web_config/sample_prompts/classic_vcs.fish b/share/tools/web_config/sample_prompts/classic_vcs.fish
index 05bcd92a5..6536e52a8 100644
--- a/share/tools/web_config/sample_prompts/classic_vcs.fish
+++ b/share/tools/web_config/sample_prompts/classic_vcs.fish
@@ -9,7 +9,7 @@ function fish_prompt --description 'Write out the prompt'
     # Color the prompt differently when we're root
     set -l color_cwd $fish_color_cwd
     set -l suffix '>'
-    if contains -- $USER root toor
+    if fish_is_root_user
         if set -q fish_color_cwd_root
             set color_cwd $fish_color_cwd_root
         end
diff --git a/share/tools/web_config/sample_prompts/debian_chroot.fish b/share/tools/web_config/sample_prompts/debian_chroot.fish
index d1b89c46f..38bd46618 100644
--- a/share/tools/web_config/sample_prompts/debian_chroot.fish
+++ b/share/tools/web_config/sample_prompts/debian_chroot.fish
@@ -4,10 +4,12 @@
 function fish_prompt --description 'Write out the prompt, prepending the Debian chroot environment if present'
     # Set variable identifying the chroot you work in (used in the prompt below)
     set -l debian_chroot $debian_chroot
+
     if not set -q debian_chroot[1]
         and test -r /etc/debian_chroot
         set debian_chroot (cat /etc/debian_chroot)
     end
+
     if not set -q __fish_debian_chroot_prompt
         and set -q debian_chroot[1]
         and test -n "$debian_chroot"
@@ -19,16 +21,15 @@ function fish_prompt --description 'Write out the prompt, prepending the Debian
         echo -n -s (set_color yellow) "$__fish_debian_chroot_prompt" (set_color normal) ' '
     end
 
-    switch "$USER"
-        case root toor
-            echo -n -s "$USER" @ (prompt_hostname) ' ' (set -q fish_color_cwd_root
-                                                        and set_color $fish_color_cwd_root
-                                                        or set_color $fish_color_cwd) (prompt_pwd) \
-                (set_color normal) '# '
+    if fish_is_root_user
+        echo -n -s "$USER" @ (prompt_hostname) ' ' (set -q fish_color_cwd_root
+                                                    and set_color $fish_color_cwd_root
+                                                    or set_color $fish_color_cwd) (prompt_pwd) \
+            (set_color normal) '# '
 
-        case '*'
-            echo -n -s "$USER" @ (prompt_hostname) ' ' (set_color $fish_color_cwd) (prompt_pwd) \
-                (set_color normal) '> '
+    else
+        echo -n -s "$USER" @ (prompt_hostname) ' ' (set_color $fish_color_cwd) (prompt_pwd) \
+            (set_color normal) '> '
 
     end
 end
diff --git a/share/tools/web_config/sample_prompts/informative.fish b/share/tools/web_config/sample_prompts/informative.fish
index d2b16c74d..02c7296ce 100644
--- a/share/tools/web_config/sample_prompts/informative.fish
+++ b/share/tools/web_config/sample_prompts/informative.fish
@@ -6,18 +6,17 @@ function fish_prompt --description 'Informative prompt'
     set -l last_pipestatus $pipestatus
     set -l last_status $status
 
-    switch "$USER"
-        case root toor
-            printf '%s@%s %s%s%s# ' $USER (prompt_hostname) (set -q fish_color_cwd_root
-                                                             and set_color $fish_color_cwd_root
-                                                             or set_color $fish_color_cwd) \
-                (prompt_pwd) (set_color normal)
-        case '*'
-            set -l pipestatus_string (__fish_print_pipestatus $last_status "[" "] " "|" (set_color $fish_color_status) \
-                                      (set_color --bold $fish_color_status) $last_pipestatus)
+    if fish_is_root_user
+        printf '%s@%s %s%s%s# ' $USER (prompt_hostname) (set -q fish_color_cwd_root
+                                                         and set_color $fish_color_cwd_root
+                                                         or set_color $fish_color_cwd) \
+            (prompt_pwd) (set_color normal)
+    else
+        set -l pipestatus_string (__fish_print_pipestatus $last_status "[" "] " "|" (set_color $fish_color_status) \
+                                  (set_color --bold $fish_color_status) $last_pipestatus)
 
-            printf '[%s] %s%s@%s %s%s %s%s%s \f\r> ' (date "+%H:%M:%S") (set_color brblue) \
-                $USER (prompt_hostname) (set_color $fish_color_cwd) $PWD $pipestatus_string \
-                (set_color normal)
+        printf '[%s] %s%s@%s %s%s %s%s%s \f\r> ' (date "+%H:%M:%S") (set_color brblue) \
+            $USER (prompt_hostname) (set_color $fish_color_cwd) $PWD $pipestatus_string \
+            (set_color normal)
     end
 end
diff --git a/share/tools/web_config/sample_prompts/informative_vcs.fish b/share/tools/web_config/sample_prompts/informative_vcs.fish
index b36c248e6..62fac6eb8 100644
--- a/share/tools/web_config/sample_prompts/informative_vcs.fish
+++ b/share/tools/web_config/sample_prompts/informative_vcs.fish
@@ -59,17 +59,16 @@ function fish_prompt --description 'Write out the prompt'
 
     set -l color_cwd
     set -l suffix
-    switch "$USER"
-        case root toor
-            if set -q fish_color_cwd_root
-                set color_cwd $fish_color_cwd_root
-            else
-                set color_cwd $fish_color_cwd
-            end
-            set suffix '#'
-        case '*'
+    if fish_is_root_user
+        if set -q fish_color_cwd_root
+            set color_cwd $fish_color_cwd_root
+        else
             set color_cwd $fish_color_cwd
-            set suffix '$'
+        end
+        set suffix '#'
+    else
+        set color_cwd $fish_color_cwd
+        set suffix '$'
     end
 
     # PWD
diff --git a/share/tools/web_config/sample_prompts/nim.fish b/share/tools/web_config/sample_prompts/nim.fish
index 3215064b3..6034bb41f 100644
--- a/share/tools/web_config/sample_prompts/nim.fish
+++ b/share/tools/web_config/sample_prompts/nim.fish
@@ -20,8 +20,8 @@ function fish_prompt
 
     # To:
     # ┬─[nim@Hattori:~/w/dashboard]─[11:37:14]─[V:django20]─[G:master↑1|●1✚1…1]─[B:85%, 05:41:42 remaining]
-    # │ 2	15054	0%	arrêtée	sleep 100000
-    # │ 1	15048	0%	arrêtée	sleep 100000
+    # │ 2    15054    0%    arrêtée    sleep 100000
+    # │ 1    15048    0%    arrêtée    sleep 100000
     # ╰─>$ echo there
 
     set -l retc red
@@ -53,19 +53,23 @@ function fish_prompt
     echo -n '┬─'
     set_color -o green
     echo -n [
-    if test "$USER" = root -o "$USER" = toor
+
+    if fish_is_root_user
         set_color -o red
     else
         set_color -o yellow
     end
+
     echo -n $USER
     set_color -o white
     echo -n @
+
     if [ -z "$SSH_CLIENT" ]
         set_color -o blue
     else
         set_color -o cyan
     end
+
     echo -n (prompt_hostname)
     set_color -o white
     echo -n :(prompt_pwd)
@@ -79,6 +83,7 @@ function fish_prompt
     # The default mode prompt would be prefixed, which ruins our alignment.
     function fish_mode_prompt
     end
+
     if test "$fish_key_bindings" = fish_vi_key_bindings
         or test "$fish_key_bindings" = fish_hybrid_key_bindings
         set -l mode
@@ -121,12 +126,14 @@ function fish_prompt
 
     # Background jobs
     set_color normal
+
     for job in (jobs)
         set_color $retc
         echo -n '│ '
         set_color brown
         echo $job
     end
+
     set_color normal
     set_color $retc
     echo -n '╰─>'