diff --git a/Koha/SearchEngine/Elasticsearch/QueryBuilder.pm b/Koha/SearchEngine/Elasticsearch/QueryBuilder.pm
index 8ee830c649..ad339ae7e4 100644
--- a/Koha/SearchEngine/Elasticsearch/QueryBuilder.pm
+++ b/Koha/SearchEngine/Elasticsearch/QueryBuilder.pm
@@ -352,7 +352,10 @@ sub build_query_compat {
         $query_cgi .= 'idx=' . uri_escape_utf8( $index // '' ) . '&q=' . uri_escape_utf8($oand);
         $query_cgi .= '&op=' . uri_escape_utf8($otor) if $otor;
     }
-    $query_cgi .= '&scan=1' if ($scan);
+    $query_cgi .= '&scan=1'                    if ($scan);
+    $query_cgi .= '&weight_search=1'           if ( $params->{weighted_fields} );
+    $query_cgi .= '&weight_search_submitted=1' if ( $params->{weight_search_submitted} );
+    $query_cgi .= '&whole_record=1'            if ( $params->{whole_record} );
 
     my $simple_query;
     $simple_query = $operands->[0] if @$operands == 1;
diff --git a/catalogue/search.pl b/catalogue/search.pl
index 762d952ae7..957a9f9dcf 100755
--- a/catalogue/search.pl
+++ b/catalogue/search.pl
@@ -277,6 +277,7 @@ if ( $template_type eq 'advsearch' ) {
         @operands  = $cgi->multi_param('q');
         @operators = @sanitized_operators;
         @indexes   = $cgi->multi_param('idx');
+        $expanded  = 1;                          # Force expanded options when editing search
         $template->param(
             sort => scalar $cgi->param('sort_by'),
         );
@@ -341,7 +342,15 @@ if ( $template_type eq 'advsearch' ) {
     {
         $expanded = C4::Context->preference("expandedSearchOption") || 0
             if !defined($expanded) || $expanded !~ /^0|1$/;
-        $template->param( expanded_options => $expanded );
+
+        # Force expanded options if weight_search_submitted or whole_record are present
+        $expanded = 1 if $cgi->param('weight_search_submitted') || $cgi->param('whole_record');
+
+        $template->param(
+            expanded_options        => $expanded,
+            weight_search_submitted => scalar $cgi->param('weight_search_submitted'),
+            whole_record            => scalar $cgi->param('whole_record'),
+        );
     }
 
     $template->param( virtualshelves => C4::Context->preference("virtualshelves") );
@@ -436,11 +445,13 @@ for ( my $ii = 0 ; $ii < @operands ; ++$ii ) {
 
 # Params that can only have one value
 my $scan             = $params->{'scan'};
-my $count            = C4::Context->preference('numSearchResults')         || 20;
-my $results_per_page = $params->{'count'}                                  || $count;
-my $offset           = $params->{'offset'}                                 || 0;
-my $whole_record     = $params->{'whole_record'}                           || 0;
-my $weight_search    = $params->{'advsearch'} ? $params->{'weight_search'} || 0 : 1;
+my $count            = C4::Context->preference('numSearchResults') || 20;
+my $results_per_page = $params->{'count'}                          || $count;
+my $offset           = $params->{'offset'}                         || 0;
+my $whole_record     = $params->{'whole_record'}                   || 0;
+my $weight_search    = $params->{'weight_search_submitted'}
+    ? ( $params->{'weight_search'} ? 1 : 0 )    # Form was submitted, use actual checkbox value
+    : 1;                                        # Form not submitted
 $offset = 0 if $offset < 0;
 
 # Define some global variables
@@ -462,7 +473,13 @@ for ( my $i = 0 ; $i < @operands ; $i++ ) {
     )
     = $builder->build_query_compat(
     \@operators, \@operands, \@indexes, \@limits,
-    \@sort_by,   $scan,      $lang, { weighted_fields => $weight_search, whole_record => $whole_record }
+    \@sort_by,
+    $scan, $lang,
+    {
+        weighted_fields         => $weight_search,
+        whole_record            => $whole_record,
+        weight_search_submitted => $params->{'weight_search_submitted'}
+    }
     );
 
 $template->param( search_query => $query ) if C4::Context->preference('DumpSearchQueryTemplate');
@@ -559,7 +576,13 @@ if ( $hits == 0 && $basic_search ) {
         )
         = $builder->build_query_compat(
         \@operators, \@operands, \@indexes, \@limits,
-        \@sort_by,   $scan,      $lang, { weighted_fields => $weight_search, whole_record => $whole_record }
+        \@sort_by,
+        $scan, $lang,
+        {
+            weighted_fields         => $weight_search,
+            whole_record            => $whole_record,
+            weight_search_submitted => $params->{'weight_search_submitted'}
+        }
         );
     my $quoted_results_hashref;
     eval {
diff --git a/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/advsearch.tt b/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/advsearch.tt
index ab6b53aac6..736eef6f95 100644
--- a/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/advsearch.tt
+++ b/koha-tmpl/intranet-tmpl/prog/en/modules/catalogue/advsearch.tt
@@ -153,13 +153,30 @@
                     [% IF ( expanded_options ) %]
                         <p>
                             [% IF Koha.Preference('ElasticsearchMARCFormat') == 'ARRAY' %]
-                                <label><input type="checkbox" name="whole_record" /> Search entire MARC record</label>
+                                <label>
+                                    [% IF whole_record %]
+                                        <input type="checkbox" name="whole_record" checked="checked" />
+                                    [% ELSE %]
+                                        <input type="checkbox" name="whole_record" />
+                                    [% END %]
+                                    Search entire MARC record</label
+                                >
                             [% END %]
                             <span id="weight_search">
-                                <label><input type="checkbox" name="weight_search" checked="checked" /> Apply field weights to search</label>
+                                <input type="hidden" name="weight_search_submitted" value="1" />
+                                <label>
+                                    [% IF weight_search_submitted && !weight_search %]
+                                        <input type="checkbox" name="weight_search" />
+                                    [% ELSE %]
+                                        [%# enabled by default or when weight_search==true %]
+                                        <input type="checkbox" name="weight_search" checked="checked" />
+                                    [% END %]
+                                    Apply field weights to search</label
+                                >
                             </span>
                         </p>
                     [% ELSE %]
+                        <input type="hidden" name="weight_search_submitted" value="1" />
                         <input type="hidden" name="weight_search" value="1" />
                     [% END %]
                 [% END %]
diff --git a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-advsearch.tt b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-advsearch.tt
index 80433b2b26..39e0ce8004 100644
--- a/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-advsearch.tt
+++ b/koha-tmpl/opac-tmpl/bootstrap/en/modules/opac-advsearch.tt
@@ -151,13 +151,20 @@
                                 [% IF ( expanded_options ) %]
                                     [% IF Koha.Preference('SearchEngine') == 'Elasticsearch' %]
                                         <div id="weight_search">
+                                            <input type="hidden" name="weight_search_submitted" value="1" />
                                             <label>
-                                                <input type="checkbox" name="weight_search" checked="checked" />
+                                                [% IF weight_search_submitted && !weight_search %]
+                                                    <input type="checkbox" name="weight_search" />
+                                                [% ELSE %]
+                                                    [%# enabled by default or when weight_search==true %]
+                                                    <input type="checkbox" name="weight_search" checked="checked" />
+                                                [% END %]
                                                 Apply field weights to search
                                             </label>
                                         </div>
                                     [% END %]
                                 [% ELSE %]
+                                    <input type="hidden" name="weight_search_submitted" value="1" />
                                     <input type="hidden" name="weight_search" value="1" />
                                 [% END %]
                                 [% IF Koha.Preference('IncludeSeeFromInSearches') %]
diff --git a/opac/opac-search.pl b/opac/opac-search.pl
index db9dc776c3..7776d1c4ad 100755
--- a/opac/opac-search.pl
+++ b/opac/opac-search.pl
@@ -216,7 +216,10 @@ if ( $cgi->cookie("search_path_code") ) {
     if ( $pathcode eq 'ads' ) {
         $template->param( 'ReturnPath' => '/cgi-bin/koha/opac-search.pl?returntosearch=1' );
     } elsif ( $pathcode eq 'exs' ) {
-        $template->param( 'ReturnPath' => '/cgi-bin/koha/opac-search.pl?expanded_options=1&returntosearch=1' );
+        my $return_params = 'expanded_options=1&returntosearch=1';
+        $return_params .= '&weight_search_submitted=1' if $cgi->param('weight_search_submitted');
+        $return_params .= '&weight_search=1'           if $cgi->param('weight_search');
+        $template->param( 'ReturnPath' => "/cgi-bin/koha/opac-search.pl?$return_params" );
     } else {
         warn "ReturnPath switch error";
     }
@@ -357,6 +360,14 @@ if ( $template_type && $template_type eq 'advsearch' ) {
         }
     }
 
+    # Force expanded options if weight_search_submitted is present
+    if ( $cgi->param('weight_search_submitted') ) {
+        $template->param( expanded_options => 1 );
+    }
+
+    # Always pass weight_search_submitted to template for checkbox logic
+    $template->param( weight_search_submitted => scalar $cgi->param('weight_search_submitted') );
+
     output_html_with_http_headers $cgi, $cookie, $template->output;
     exit;
 }
@@ -494,7 +505,9 @@ $offset = 0 if $offset < 0;
 my $page = $cgi->param('page') || 1;
 $offset = ( $page - 1 ) * $results_per_page if $page > 1;
 my $hits;
-my $weight_search = $cgi->param('advsearch') ? $cgi->param('weight_search') || 0 : 1;
+my $weight_search = $cgi->param('weight_search_submitted')
+    ? ( $cgi->param('weight_search') ? 1 : 0 )    # Form was submitted, use actual checkbox value
+    : 1;                                          # Form not submitted
 
 # Define some global variables
 my ( $error, $query, $simple_query, $query_cgi, $query_desc, $limit, $limit_cgi, $limit_desc, $query_type );
@@ -523,9 +536,10 @@ if ( C4::Context->preference('OpacSuppression') ) {
     0,
     $lang,
     {
-        suppress        => $suppress,
-        is_opac         => 1,
-        weighted_fields => $weight_search
+        suppress                => $suppress,
+        is_opac                 => 1,
+        weighted_fields         => $weight_search,
+        weight_search_submitted => $cgi->param('weight_search_submitted')
     }
     );
 
@@ -644,9 +658,10 @@ for ( my $i = 0 ; $i < @servers ; $i++ ) {
                 0,
                 $lang,
                 {
-                    suppress        => $suppress,
-                    is_opac         => 1,
-                    weighted_fields => $weight_search
+                    suppress                => $suppress,
+                    is_opac                 => 1,
+                    weighted_fields         => $weight_search,
+                    weight_search_submitted => $cgi->param('weight_search_submitted')
                 }
                 );
             my $quoted_results_hashref;