diff --git a/koha-tmpl/intranet-tmpl/prog/en/modules/members/boraccount.tt b/koha-tmpl/intranet-tmpl/prog/en/modules/members/boraccount.tt
index 25c9a152e8..4728744f58 100644
--- a/koha-tmpl/intranet-tmpl/prog/en/modules/members/boraccount.tt
+++ b/koha-tmpl/intranet-tmpl/prog/en/modules/members/boraccount.tt
@@ -646,6 +646,25 @@
                 $("#returned, #refund_type").focus();
             });
 
+            // Validate cash register requirement for refunds
+            [% IF Koha.Preference('UseCashRegisters') %]
+                $("#refund_form").on("submit", function(e) {
+                    var refund_type = $("#refund_type").val();
+                    var register = $("#refund_registerid").val();
+
+                    // Only require register for non-AC refunds with CASH or SIP00 payment types
+                    if (refund_type && refund_type !== 'AC' && (refund_type === 'CASH' || refund_type.match(/^SIP\d{2}$/))) {
+                        if (!register || register === '') {
+                            e.preventDefault();
+                            alert(_("Cash register is required for cash refunds"));
+                            $("#refund_registerid").focus();
+                            return false;
+                        }
+                    }
+                    return true;
+                });
+            [% END %]
+
             $("#applyDiscountModal").on("shown.bs.modal", function (e) {
                 var button = $(e.relatedTarget);
                 var item = button.data("item");
diff --git a/pos/register.pl b/pos/register.pl
index 3e785dbf18..3b162746e1 100755
--- a/pos/register.pl
+++ b/pos/register.pl
@@ -138,19 +138,24 @@ if ( !$registers->count ) {
                             amount         => $amount
                         }
                     );
-                    my $payout = $refund->payout(
-                        {
-                            payout_type   => $refund_type,
-                            branch        => $library_id,
-                            staff_id      => $logged_in_user->id,
-                            cash_register => $cash_register->id,
-                            interface     => 'intranet',
-                            amount        => $amount
-                        }
-                    );
-
+                    unless ( $refund_type eq 'AC' ) {
+                        my $payout = $refund->payout(
+                            {
+                                payout_type   => $refund_type,
+                                branch        => $library_id,
+                                staff_id      => $logged_in_user->id,
+                                cash_register => $registerid,
+                                interface     => 'intranet',
+                                amount        => $amount
+                            }
+                        );
+                    }
                 }
             );
+
+            # Redirect to prevent duplicate submissions (POST/REDIRECT/GET pattern)
+            print $input->redirect( "/cgi-bin/koha/pos/register.pl?registerid=" . $registerid );
+            exit;
         } else {
             $template->param( error_refund_permission => 1 );
         }