diff --git a/admin/categorie.pl b/admin/categorie.pl
index 27e95cb1f5..a848aa4f0b 100755
--- a/admin/categorie.pl
+++ b/admin/categorie.pl
@@ -42,9 +42,9 @@ use C4::Context;
 use C4::Auth;
 use C4::Branch;
 use C4::Output;
-use C4::Dates;
 use C4::Form::MessagingPreferences;
 use Koha::Database;
+use Koha::DateUtils;
 
 sub StringSearch {
     my ( $searchstring, $type ) = @_;
@@ -172,11 +172,9 @@ elsif ( $op eq 'add_validate' ) {
     my $dbh = C4::Context->dbh;
 
     if ( $input->param('enrolmentperioddate') ) {
-        $input->param(
-            'enrolmentperioddate' => C4::Dates::format_date_in_iso(
-                $input->param('enrolmentperioddate')
-            )
-        );
+        my $enrolment_dt = eval { dt_from_string( $input->param('enrolmentperioddate') ) };
+        $enrolment_dt = eval { output_pref( { dt => $enrolment_dt, dateonly => 1, dateformat => 'iso' } ) } if ( $enrolment_dt );
+        $input->param( 'enrolmentperioddate' => $enrolment_dt );
     }
 
     if ($is_a_modif) {
diff --git a/admin/smart-rules.pl b/admin/smart-rules.pl
index de090cb2a0..05c81d51a6 100755
--- a/admin/smart-rules.pl
+++ b/admin/smart-rules.pl
@@ -26,7 +26,7 @@ use C4::Auth;
 use C4::Koha;
 use C4::Debug;
 use C4::Branch; # GetBranches
-use C4::Dates qw/format_date format_date_in_iso/;
+use Koha::DateUtils;
 use Koha::Database;
 
 my $input = CGI->new;
@@ -126,8 +126,8 @@ elsif ($op eq 'add') {
     $maxonsiteissueqty = undef if $maxonsiteissueqty !~ /^\d+/;
     my $issuelength  = $input->param('issuelength');
     my $lengthunit  = $input->param('lengthunit');
-    my $hardduedate = $input->param('hardduedate');
-    $hardduedate = format_date_in_iso($hardduedate);
+    my $hardduedate = eval { dt_from_string( $input->param('hardduedate') ) };
+    $hardduedate = output_pref( { dt => $hardduedate, dateonly => 1, dateformat => 'iso' } ) if ( $hardduedate );
     my $hardduedatecompare = $input->param('hardduedatecompare');
     my $rentaldiscount = $input->param('rentaldiscount');
     my $opacitemholds = $input->param('opacitemholds') || 0;
@@ -446,7 +446,8 @@ while (my $row = $sth2->fetchrow_hashref) {
     $row->{'default_humancategorycode'} = 1 if $row->{'humancategorycode'} eq '*';
     $row->{'fine'} = sprintf('%.2f', $row->{'fine'});
     if ($row->{'hardduedate'} && $row->{'hardduedate'} ne '0000-00-00') {
-       $row->{'hardduedate'} = format_date( $row->{'hardduedate'});
+       my $harddue_dt = eval { dt_from_string( $row->{'hardduedate'} ) };
+       $row->{'hardduedate'} = eval { output_pref( { dt => $harddue_dt, dateonly => 1 } ) } if ( $harddue_dt );
        $row->{'hardduedatebefore'} = 1 if ($row->{'hardduedatecompare'} == -1);
        $row->{'hardduedateexact'} = 1 if ($row->{'hardduedatecompare'} ==  0);
        $row->{'hardduedateafter'} = 1 if ($row->{'hardduedatecompare'} ==  1);