diff --git a/core/boxes/box_mahnung_offen.php b/core/boxes/box_mahnung_offen.php
index 602e9fa..d2cfb1e 100644
--- a/core/boxes/box_mahnung_offen.php
+++ b/core/boxes/box_mahnung_offen.php
@@ -80,7 +80,10 @@ class box_mahnung_offen extends ModeleBoxes
 		$sql .= "  ORDER BY m2.stufe DESC LIMIT 1) as mahnstufe,";
 		$sql .= " (SELECT m3.date_mahnung FROM ".MAIN_DB_PREFIX."mahnung_mahnung as m3";
 		$sql .= "  WHERE m3.fk_facture = f.rowid AND m3.status != ".((int) Mahnung::STATUS_STORNIERT);
-		$sql .= "  ORDER BY m3.stufe DESC LIMIT 1) as mahndatum";
+		$sql .= "  ORDER BY m3.stufe DESC LIMIT 1) as mahndatum,";
+		$sql .= " (SELECT m4.rowid FROM ".MAIN_DB_PREFIX."mahnung_mahnung as m4";
+		$sql .= "  WHERE m4.fk_facture = f.rowid AND m4.status != ".((int) Mahnung::STATUS_STORNIERT);
+		$sql .= "  ORDER BY m4.stufe DESC LIMIT 1) as mahnid";
 		$sql .= " FROM ".MAIN_DB_PREFIX."facture as f";
 		$sql .= " INNER JOIN ".MAIN_DB_PREFIX."societe as s ON s.rowid = f.fk_soc";
 		$sql .= " LEFT JOIN ".MAIN_DB_PREFIX."paiement_facture as pf ON f.rowid = pf.fk_facture";
@@ -145,8 +148,8 @@ class box_mahnung_offen extends ModeleBoxes
 				$late = img_warning(sprintf($l_due_date, dol_print_date($datelimit, 'day', 'tzuserrel')));
 			}
 
-			// Mahnstufe-Badge
-			$mahnBadge = '';
+			// Mahnstufe-Badge (mit Link zur Mahnung) oder Strich fuer keine Mahnung
+			$mahnCell = '<span class="opacitymedium">—</span>';
 			if (!empty($objp->mahnstufe)) {
 				$stufe = (int) $objp->mahnstufe;
 				$colors = array(1 => '#4a90d9', 2 => '#e68a00', 3 => '#cc3333');
@@ -155,7 +158,12 @@ class box_mahnung_offen extends ModeleBoxes
 				$label = $labels[$stufe] ?? 'Stufe '.$stufe;
 				$mahnDatum = $objp->mahndatum ? dol_print_date($this->db->jdate($objp->mahndatum), 'day') : '';
 				$tooltip = $label.($mahnDatum ? ' vom '.$mahnDatum : '');
-				$mahnBadge = '<span class="badge" style="background-color:'.$color.';color:#fff;font-size:0.75em;" title="'.dol_escape_htmltag($tooltip).'">'.$label.'</span>';
+				$badge = '<span class="badge" style="background-color:'.$color.';color:#fff;font-size:0.75em;" title="'.dol_escape_htmltag($tooltip).'">'.$label.'</span>';
+				if (!empty($objp->mahnid)) {
+					$mahnCell = '<a href="'.DOL_URL_ROOT.'/custom/mahnung/card.php?id='.((int) $objp->mahnid).'">'.$badge.'</a>';
+				} else {
+					$mahnCell = $badge;
+				}
 			}
 
 			// Spalte 1: Rechnung + Warnung
@@ -188,7 +196,7 @@ class box_mahnung_offen extends ModeleBoxes
 			// Spalte 5: Mahnstufe
 			$this->info_box_contents[$line][] = array(
 				'td' => 'class="center nowraponall"',
-				'text' => !empty($mahnBadge) ? $mahnBadge : '',
+				'text' => $mahnCell,
 				'asis' => 1,
 			);