diff --git a/share/html/Admin/CustomFields/Modify.html b/share/html/Admin/CustomFields/Modify.html
index 6e35d8da722..904eaea04d4 100644
--- a/share/html/Admin/CustomFields/Modify.html
+++ b/share/html/Admin/CustomFields/Modify.html
@@ -181,7 +181,7 @@
 % if ( $CustomFieldObj->SupportDefaultValues ) {
 <&| /Elements/LabeledValue, Label => loc("Default [numerate,_1,value,values]", $CustomFieldObj->MaxValues),
     Class => $default_value_class &>
-  <& /Elements/EditCustomField, NamePrefix => 'Default-', CustomField => $CustomFieldObj, ShowEmptyOption => 1 &>
+  <& /Elements/EditCustomField, NamePrefix => 'Default-', CustomField => $CustomFieldObj, ShowEmptyOption => 1, Required => 0 &>
 </&>
 % }
 
diff --git a/share/html/Admin/Queues/DefaultValues.html b/share/html/Admin/Queues/DefaultValues.html
index 0cde0c46ddd..3f69b0fb2ec 100644
--- a/share/html/Admin/Queues/DefaultValues.html
+++ b/share/html/Admin/Queues/DefaultValues.html
@@ -68,6 +68,8 @@
       CustomFields => $queue->TicketCustomFields->LimitToDefaultValuesSupportedTypes,
       Grouping => 'Basics',
       CategoryObj => $queue,
+      ShowEmptyOption => 1,
+      Required => 0,
   &>
 
   <&| /Elements/LabeledValue, Label => loc('Article') &>
@@ -91,6 +93,8 @@
       CustomFields => $queue->TicketCustomFields->LimitToDefaultValuesSupportedTypes,
       Grouping => 'Dates',
       CategoryObj => $queue,
+      ShowEmptyOption => 1,
+      Required => 0,
   &>
   </&>
 </div>
@@ -103,6 +107,8 @@
       CustomFields => $queue->TicketCustomFields->LimitToDefaultValuesSupportedTypes,
       Grouping => 'People',
       CategoryObj => $queue,
+      ShowEmptyOption => 1,
+      Required => 0,
   &>
   </&>
 </div>
@@ -116,6 +122,8 @@
       CustomFields => $queue->TicketCustomFields->LimitToDefaultValuesSupportedTypes,
       Grouping => 'Links',
       CategoryObj => $queue,
+      ShowEmptyOption => 1,
+      Required => 0,
   &>
   </&>
 </div>
@@ -126,11 +134,13 @@
     Object => RT::Ticket->new($session{CurrentUser}),
     Groupings => \@groupings,
     CategoryObj => $queue,
+    ShowEmptyOption => 1,
+    Required => 0,
 &>
 
 <div class="ticket-info-cfs">
   <&|/Widgets/TitleBox, title => loc("Transaction Custom Fields"), content_class => 'mx-auto width-sm' &>
-  <& /Elements/EditCustomFields, CustomFields => $queue->TicketTransactionCustomFields->LimitToDefaultValuesSupportedTypes, Object => RT::Transaction->new($session{CurrentUser}), QueueObj => $queue, &>
+  <& /Elements/EditCustomFields, CustomFields => $queue->TicketTransactionCustomFields->LimitToDefaultValuesSupportedTypes, Object => RT::Transaction->new($session{CurrentUser}), QueueObj => $queue, ShowEmptyOption => 1, Required => 0 &>
   </&>
 </div>
 
diff --git a/share/html/Elements/EditCustomField b/share/html/Elements/EditCustomField
index c088917ee70..b2e75720642 100644
--- a/share/html/Elements/EditCustomField
+++ b/share/html/Elements/EditCustomField
@@ -162,4 +162,5 @@ $Rows        => 5
 $Cols        => 15
 $Default     => undef
 $DefaultsFromTopArguments => 1,
+$Required    => undef
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldAutocomplete b/share/html/Elements/EditCustomFieldAutocomplete
index 40104555ae7..2acef923d7c 100644
--- a/share/html/Elements/EditCustomFieldAutocomplete
+++ b/share/html/Elements/EditCustomFieldAutocomplete
@@ -53,6 +53,9 @@ cols="<% $Cols %>" \
 % if ( defined $Rows ) {
 rows="<% $Rows %>" \
 % }
+% if ( $Required ) {
+required
+% }
 name="<% $name %>" id="<% $name %>" class="CF-<%$CustomField->id%>-Edit form-control"><% $Default || '' %></textarea>
 
 <script type="text/javascript">
@@ -78,7 +81,11 @@ jQuery('#'+id).autocomplete( {
 }
 );
 % } else {
-<input type="text" id="<% $name %>" name="<% $name %>" class="CF-<%$CustomField->id%>-Edit form-control" value="<% $Default || '' %>"/>
+<input type="text" id="<% $name %>" name="<% $name %>" class="CF-<%$CustomField->id%>-Edit form-control" value="<% $Default || '' %>"
+% if ( $Required ) {
+  required
+% }
+/>
 <script type="text/javascript">
 var id = <% $name |n,j%>;
 id = id.replace(/:/g,'\\:');
@@ -114,4 +121,5 @@ $Values      => undef
 $Multiple    => undef
 $Rows        => undef
 $Cols        => undef
+$Required    => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldBinary b/share/html/Elements/EditCustomFieldBinary
index 87f74913a46..60f3d88facc 100644
--- a/share/html/Elements/EditCustomFieldBinary
+++ b/share/html/Elements/EditCustomFieldBinary
@@ -68,7 +68,11 @@
 % }
 
 <div class="custom-file">
-  <input type="file" id="<% $name %>" name="<% $name %>" class="CF-<%$CustomField->id%>-Edit custom-file-input" />
+  <input type="file" id="<% $name %>" name="<% $name %>" class="CF-<%$CustomField->id%>-Edit custom-file-input"
+% if ( $Required ) {
+    required
+% }
+  />
   <label class="custom-file-label" for="<% $name %>"><&|/l&>Choose file</&></label>
 </div>
 
@@ -86,4 +90,5 @@ $Name   => undef
 $Default => undef
 $Values => undef
 $MaxValues => undef
+$Required => ( ( $Values && $Values->Count ) || $CustomField->MatchPattern('') ) ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldCombobox b/share/html/Elements/EditCustomFieldCombobox
index b0653885a14..5422ebb568c 100644
--- a/share/html/Elements/EditCustomFieldCombobox
+++ b/share/html/Elements/EditCustomFieldCombobox
@@ -58,6 +58,7 @@
     Rows    => $Rows,
     Class   => "CF-".$CustomField->id."-Edit",
     Values  => [map {$_->Name} @{CachedCustomFieldValues($CustomField)->ItemsArrayRef}],
+    Required => $Required,
 &>
 
 <%INIT>
@@ -76,4 +77,5 @@ $Multiple => 0
 $Rows => undef
 $MaxValues => undef
 $Name => undef
+$Required => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldDate b/share/html/Elements/EditCustomFieldDate
index 7b99dba0b06..cceacb1ba23 100644
--- a/share/html/Elements/EditCustomFieldDate
+++ b/share/html/Elements/EditCustomFieldDate
@@ -48,7 +48,7 @@
 % my $name = $Name || $NamePrefix.$CustomField->Id.'-Values';
 <div class="form-row">
   <div class="col-auto">
-    <& /Elements/SelectDate, Name => $name, Default => $Default, current => 0, ShowTime => 0 &>
+    <& /Elements/SelectDate, Name => $name, Default => $Default, current => 0, ShowTime => 0, Required => $Required, &>
   </div>
   <div class="col-auto">
     <span class="current-value form-control">(<%$DateObj->AsString(Time => 0, Timezone => 'utc')%>)</span>
@@ -66,4 +66,5 @@ $Default => undef
 $Values => undef
 $MaxValues => 1
 $Name => undef
+$Required => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldDateTime b/share/html/Elements/EditCustomFieldDateTime
index ac41403e51c..f3f8129ade2 100644
--- a/share/html/Elements/EditCustomFieldDateTime
+++ b/share/html/Elements/EditCustomFieldDateTime
@@ -48,7 +48,7 @@
 % my $name = $Name || $NamePrefix.$CustomField->Id.'-Values';
 <div class="form-row">
     <div class="col-auto">
-        <& /Elements/SelectDate, Name => $name, Default => $Default, current => 0 &>
+        <& /Elements/SelectDate, Name => $name, Default => $Default, current => 0, Required => $Required, &>
     </div>
     <div class="col-auto">
         <span class="current-value form-control">(<%$DateObj->AsString%>)</span>
@@ -68,4 +68,5 @@ $Values => undef
 $MaxValues => 1
 $Name => undef
 $Format => 'unknown'
+$Required => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldFreeform b/share/html/Elements/EditCustomFieldFreeform
index c7c5ed18744..85345f3de7b 100644
--- a/share/html/Elements/EditCustomFieldFreeform
+++ b/share/html/Elements/EditCustomFieldFreeform
@@ -54,12 +54,18 @@ cols="<% $Cols %>" \
 % if ( defined $Rows ) {
 rows="<% $Rows %>" \
 % }
+% if ( $Required ) {
+required
+% }
 name="<%$name%>" id="<%$name%>" wrap="off" class="CF-<%$CustomField->id%>-Edit form-control"><% defined($Default) ? $Default : '' %></textarea>
 % } else {
 <input type="text" name="<%$name%>" id="<%$name%>" \
 % if ( defined $Cols ) {
 size="<% $Cols %>" \
 % }
+% if ( $Required ) {
+required
+% }
 class="CF-<%$CustomField->id%>-Edit form-control" value="<% defined($Default) ? $Default : ''%>" />
 % }
 <%INIT>
@@ -80,4 +86,5 @@ $Values => undef
 $Multiple => undef
 $Cols
 $Rows
+$Required => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldHTML b/share/html/Elements/EditCustomFieldHTML
index 90200b6bdfc..2f74612ca18 100644
--- a/share/html/Elements/EditCustomFieldHTML
+++ b/share/html/Elements/EditCustomFieldHTML
@@ -64,6 +64,9 @@ cols="<% $Cols %>" \
 % if ( defined $Rows ) {
 rows="<% $Rows %>" \
 % }
+% if ( $Required ) {
+required
+% }
 name="<%$name%>" class="CF-<%$CustomField->id%>-Edit form-control richtext"><% $Default %></textarea>
 % }
 <%INIT>
@@ -81,4 +84,5 @@ $Values => undef
 $MaxValues => undef
 $Cols
 $Rows
+$Required => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldImage b/share/html/Elements/EditCustomFieldImage
index 478bade2f6c..5efac3f9c06 100644
--- a/share/html/Elements/EditCustomFieldImage
+++ b/share/html/Elements/EditCustomFieldImage
@@ -60,7 +60,11 @@
 % }
 
 <div class="custom-file">
-  <input type="file" id="<% $name %>" name="<% $name %>" class="CF-<%$CustomField->id%>-Edit custom-file-input" />
+  <input type="file" id="<% $name %>" name="<% $name %>" class="CF-<%$CustomField->id%>-Edit custom-file-input"
+% if ( $Required ) {
+    required
+% }
+  />
   <label class="custom-file-label" for="<% $name %>"><&|/l&>Choose file</&></label>
 </div>
 
@@ -78,4 +82,5 @@ $Name => undef
 $Default => undef
 $Values => undef
 $MaxValues => undef
+$Required => ( ( $Values && $Values->Count ) || $CustomField->MatchPattern('') ) ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldSelect b/share/html/Elements/EditCustomFieldSelect
index 9921e5e965f..8caf1c1355a 100644
--- a/share/html/Elements/EditCustomFieldSelect
+++ b/share/html/Elements/EditCustomFieldSelect
@@ -72,7 +72,7 @@
 %     my $content = $value->Name;
 %     my $labelid = "$name-". $value->id;
 <div data-name="<% $value->Category || '' %>" class="custom-control custom-<% $checktype %>">
-  <input class="custom-control-input"  type="<% $checktype %>" name="<% $name %>" id="<% $labelid %>" value="<% $content %>" <% $default{ lc $content }? ' checked="checked"' : '' |n%> />
+  <input class="custom-control-input"  type="<% $checktype %>" name="<% $name %>" id="<% $labelid %>" value="<% $content %>" <% $default{ lc $content }? ' checked="checked"' : '' |n%> <% $checktype eq 'radio' && $Required ? 'required' : '' %>/>
   <label class="custom-control-label" for="<% $labelid %>"><% $content %></label><br />
 </div>
 %   }
@@ -85,7 +85,7 @@
 %   my $TrueValue  = ( $checkbox_value = $CFVs->Next ) ? $checkbox_value->Name : 'True';
 %   my $isChecked = (scalar keys %default) && (not exists $default{lc $FalseValue});
   <div class="custom-control custom-checkbox">
-    <input id="<% $name . '-Display' %>" type="checkbox" class="custom-control-input" data-checked-value="<% $TrueValue %>" data-unchecked-value="<% $FalseValue %>" value-target="#<% $name %>" <% $isChecked ? "checked" : "" %> />
+    <input id="<% $name . '-Display' %>" type="checkbox" class="custom-control-input" data-checked-value="<% $TrueValue %>" data-unchecked-value="<% $FalseValue %>" value-target="#<% $name %>" <% $isChecked ? "checked" : "" %> <% $Required && !$CustomField->MatchPattern($FalseValue) ? 'required' : '' %> />
     <label class="custom-control-label" for="<% $name . '-Display' %>"></label>
     <input type="hidden" id="<% $name %>" name="<% $name %>" class="custom-control" value="<% $isChecked ? $TrueValue : $FalseValue %>" />
   </div>
@@ -123,6 +123,9 @@
 % if ( $size > 1 ) {
   size="<% $Rows %>"
 % }
+% if ( $Required ) {
+  required
+% }
 <% $Multiple && qq[multiple="multiple"] |n %> >
 % if ( $show_empty_option ) {
 <option value=""<% !$selected && qq[ selected="selected"] |n %>><&|/l&>(no value)</&></option>
@@ -164,11 +167,6 @@ else {
     if ( $CustomField->MatchPattern('') ) {
         $show_empty_option = 1;
     }
-    elsif ( $CustomField->SupportDefaultValues ) {
-        my ( $on ) = grep { $_->isa( $CustomField->RecordClassFromLookupType ) } $CustomField->ACLEquivalenceObjects;
-        my $default_values = $CustomField->DefaultValues( Object => $on || RT->System );
-        $show_empty_option = 1 unless defined $default_values && length $default_values;
-    }
 }
 
 my $use_chosen = CachedCustomFieldValues($CustomField)->Count >= 10 ? 1 : 0;
@@ -191,6 +189,7 @@ $Rows => undef
 $HideCategory => 0
 $RenderType => undef
 $MaxValues => 1
+$Required => $CustomField->MatchPattern('') ? 0 : 1,
 </%ARGS>
 
 <%METHOD options>
diff --git a/share/html/Elements/EditCustomFieldText b/share/html/Elements/EditCustomFieldText
index ac365b6ad4a..eea620a927f 100644
--- a/share/html/Elements/EditCustomFieldText
+++ b/share/html/Elements/EditCustomFieldText
@@ -63,6 +63,9 @@ cols="<% $Cols %>" \
 % if ( defined $Rows ) {
 rows="<% $Rows %>" \
 % }
+% if ( $Required ) {
+required
+% }
 name="<%$name%>" class="CF-<%$CustomField->id%>-Edit form-control"><% defined($Default) ? $Default : '' %></textarea>
 % }
 <%INIT>
@@ -80,4 +83,5 @@ $Values => undef
 $MaxValues => undef
 $Cols
 $Rows
+$Required => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFieldWikitext b/share/html/Elements/EditCustomFieldWikitext
index d28add1c2b2..27fe1521947 100644
--- a/share/html/Elements/EditCustomFieldWikitext
+++ b/share/html/Elements/EditCustomFieldWikitext
@@ -63,6 +63,9 @@ cols="<% $Cols %>" \
 % if ( defined $Rows ) {
 rows="<% $Rows %>" \
 % }
+% if ( $Required ) {
+required
+% }
 name="<%$name%>" class="CF-<%$CustomField->id%>-Edit form-control"><% $Default %></textarea>
 % }
 <%INIT>
@@ -80,4 +83,5 @@ $Values => undef
 $MaxValues => undef
 $Cols
 $Rows
+$Required => $CustomField->MatchPattern('') ? 0 : 1
 </%ARGS>
diff --git a/share/html/Elements/EditCustomFields b/share/html/Elements/EditCustomFields
index fdecf23507f..12f76cd6a65 100644
--- a/share/html/Elements/EditCustomFields
+++ b/share/html/Elements/EditCustomFields
@@ -125,4 +125,5 @@ $LabelCols => 3
 $ValueCols => 9
 $ShowHints => 1
 $ForCreation => 0
+$Required => undef
 </%ARGS>
diff --git a/share/html/Elements/SelectDate b/share/html/Elements/SelectDate
index 1425e1bcefb..af7e0476543 100644
--- a/share/html/Elements/SelectDate
+++ b/share/html/Elements/SelectDate
@@ -49,6 +49,9 @@
 <input type="text" class="datepicker<% $ShowTime ? ' withtime' : '' %> form-control"
 % if ( $id ) {
  id="<% $id %>"
+% }
+% if ( $Required ) {
+required
 % }
  name="<% $Name %>" value="<% $Default %>" size="<% $Size %>" autocomplete="off" />
 % $m->callback( %ARGS, Name => $Name, CallbackName => 'AfterDateInput', Object => $Object, ARGSRef => $ARGSRef, );
@@ -78,4 +81,5 @@ $Size        => 16
 $Object      => undef
 $ARGSRef     => undef
 $id          => undef
+$Required    => undef
 </%args>
diff --git a/share/html/Widgets/ComboBox b/share/html/Widgets/ComboBox
index 681e763ce69..9c3c7cfbd55 100644
--- a/share/html/Widgets/ComboBox
+++ b/share/html/Widgets/ComboBox
@@ -51,7 +51,7 @@ my $z_index = 9999;
 </%once>
 
 <div class="combobox-wrapper" data-name="<% $Name %>" data-value="<% $Default // '' %>">
-  <select class="form-control combobox" size="<% $Rows %>">
+  <select class="form-control combobox" size="<% $Rows %>" <% $Required ? 'required' : '' %>>
     <option value=""></option>
 % for my $value (@Values) {
     <option value="<% $value %>" <% ($Default // '') eq $value ? 'selected="selected"' : '' %>><% $value%></option>
@@ -65,4 +65,5 @@ $Rows    => 5
 $Default => ''
 @Values  => ()
 $Class   => ''
+$Required => undef
 </%ARGS>
diff --git a/share/static/js/cascaded.js b/share/static/js/cascaded.js
index d9596cbd5d1..c18850cfed5 100644
--- a/share/static/js/cascaded.js
+++ b/share/static/js/cascaded.js
@@ -79,6 +79,11 @@ function filter_cascade_select (select, complete_select, vals) {
         }
     }
 
+    // Do not automatically select the first option for required selects as they don't have empty option
+    if ( jQuery(select).is('[required]') && !jQuery(select).find('option[selected]').length ) {
+        jQuery(select).val(null);
+    }
+
     if ( jQuery(select).closest('div.bootstrap-select').length ) {
         refreshSelectpicker(jQuery(select));
     }
diff --git a/share/static/js/util.js b/share/static/js/util.js
index d349bd6dcc9..a7dd4192f9b 100644
--- a/share/static/js/util.js
+++ b/share/static/js/util.js
@@ -1021,6 +1021,16 @@ jQuery(function() {
             form.addClass('rt-form-submitted');
         });
     });
+
+    // Do not automatically select the first option for required selects as they don't have empty option
+    jQuery('select[required]').each(function () {
+        if ( !jQuery(this).find('option[selected]').length ) {
+            jQuery(this).val(null);
+            if ( jQuery(this).closest('div.bootstrap-select').length ) {
+                refreshSelectpicker(jQuery(this));
+            }
+        }
+    });
 });
 
 function filterSearchResults () {