diff --git a/frontend/src/components/events/ParticipantsSidebar.jsx b/frontend/src/components/events/ParticipantsSidebar.jsx
index 06468ef..39938ce 100644
--- a/frontend/src/components/events/ParticipantsSidebar.jsx
+++ b/frontend/src/components/events/ParticipantsSidebar.jsx
@@ -43,6 +43,21 @@ const ParticipantsSidebar = ({
   const participantCount = users.length;
   const onlineCount = activeUsers.length;
 
+  // Group users by status for better UX
+  const groupedUsers = users.reduce((groups, user) => {
+    const hasHeats = (userHeats.get(user.userId) || []).length > 0;
+    const isOnline = user.isOnline ?? false;
+
+    if (isOnline && hasHeats) {
+      groups.onlineWithHeats.push(user);
+    } else if (isOnline && !hasHeats) {
+      groups.onlineNoHeats.push(user);
+    } else {
+      groups.offline.push(user);
+    }
+    return groups;
+  }, { onlineWithHeats: [], onlineNoHeats: [], offline: [] });
+
   return (
     <div className={`${fullWidth ? 'w-full' : 'w-64 border-r'} bg-gray-50 p-4 overflow-y-auto ${className}`}>
       {/* Header */}
@@ -78,38 +93,129 @@ const ParticipantsSidebar = ({
         <p className="text-sm text-gray-500">No other participants</p>
       )}
 
-      {/* User List */}
-      <div className="space-y-2">
-        {users.map((displayUser) => {
-          const thisUserHeats = userHeats.get(displayUser.userId) || [];
-          const competitorNumber = userCompetitorNumbers.get(displayUser.userId);
-          const hasHeats = thisUserHeats.length > 0;
+      {/* User List - Grouped by Status */}
+      <div className="space-y-4">
+        {/* Online with Heats - Ready to match */}
+        {groupedUsers.onlineWithHeats.length > 0 && (
+          <div>
+            <div className="flex items-center gap-2 mb-2">
+              <div className="w-2 h-2 bg-green-500 rounded-full"></div>
+              <h4 className="text-xs font-semibold text-gray-700 uppercase tracking-wider">
+                Available ({groupedUsers.onlineWithHeats.length})
+              </h4>
+            </div>
+            <div className="space-y-1">
+              {groupedUsers.onlineWithHeats.map((displayUser) => {
+                const thisUserHeats = userHeats.get(displayUser.userId) || [];
+                const competitorNumber = userCompetitorNumbers.get(displayUser.userId);
 
-          return (
-            <UserListItem
-              key={displayUser.userId}
-              user={displayUser}
-              heats={thisUserHeats}
-              competitorNumber={competitorNumber}
-              showHeats={true}
-              linkToProfile={true}
-              actionButton={
-                <button
-                  onClick={() => onMatchWith?.(displayUser.userId)}
-                  disabled={!hasHeats}
-                  className={`p-1 rounded flex-shrink-0 ${
-                    hasHeats
-                      ? 'text-primary-600 hover:bg-primary-50'
-                      : 'text-gray-300 cursor-not-allowed'
-                  }`}
-                  title={hasHeats ? 'Connect' : 'User has not declared heats'}
-                >
-                  <UserPlus className="w-4 h-4" />
-                </button>
-              }
-            />
-          );
-        })}
+                return (
+                  <UserListItem
+                    key={displayUser.userId}
+                    user={displayUser}
+                    heats={thisUserHeats}
+                    competitorNumber={competitorNumber}
+                    showHeats={true}
+                    linkToProfile={true}
+                    actionButton={
+                      <button
+                        onClick={() => onMatchWith?.(displayUser.userId)}
+                        className="p-1 rounded flex-shrink-0 text-primary-600 hover:bg-primary-50"
+                        title="Send match request"
+                      >
+                        <UserPlus className="w-4 h-4" />
+                      </button>
+                    }
+                  />
+                );
+              })}
+            </div>
+          </div>
+        )}
+
+        {/* Online without Heats - Can't match yet */}
+        {groupedUsers.onlineNoHeats.length > 0 && (
+          <div>
+            <div className="flex items-center gap-2 mb-2">
+              <div className="w-2 h-2 bg-yellow-500 rounded-full"></div>
+              <h4 className="text-xs font-semibold text-gray-700 uppercase tracking-wider">
+                Online - No Heats ({groupedUsers.onlineNoHeats.length})
+              </h4>
+            </div>
+            <div className="space-y-1">
+              {groupedUsers.onlineNoHeats.map((displayUser) => {
+                const competitorNumber = userCompetitorNumbers.get(displayUser.userId);
+
+                return (
+                  <UserListItem
+                    key={displayUser.userId}
+                    user={displayUser}
+                    heats={[]}
+                    competitorNumber={competitorNumber}
+                    showHeats={true}
+                    linkToProfile={true}
+                    actionButton={
+                      <div
+                        className="p-1 rounded flex-shrink-0 text-gray-300 cursor-not-allowed"
+                        title="User has not declared heats yet"
+                      >
+                        <UserPlus className="w-4 h-4" />
+                      </div>
+                    }
+                  />
+                );
+              })}
+            </div>
+          </div>
+        )}
+
+        {/* Offline */}
+        {groupedUsers.offline.length > 0 && (
+          <div>
+            <div className="flex items-center gap-2 mb-2">
+              <div className="w-2 h-2 bg-gray-400 rounded-full"></div>
+              <h4 className="text-xs font-semibold text-gray-700 uppercase tracking-wider">
+                Offline ({groupedUsers.offline.length})
+              </h4>
+            </div>
+            <div className="space-y-1">
+              {groupedUsers.offline.map((displayUser) => {
+                const thisUserHeats = userHeats.get(displayUser.userId) || [];
+                const competitorNumber = userCompetitorNumbers.get(displayUser.userId);
+                const hasHeats = thisUserHeats.length > 0;
+
+                return (
+                  <UserListItem
+                    key={displayUser.userId}
+                    user={displayUser}
+                    heats={thisUserHeats}
+                    competitorNumber={competitorNumber}
+                    showHeats={true}
+                    linkToProfile={true}
+                    actionButton={
+                      hasHeats ? (
+                        <button
+                          onClick={() => onMatchWith?.(displayUser.userId)}
+                          className="p-1 rounded flex-shrink-0 text-primary-600 hover:bg-primary-50 opacity-60"
+                          title="Send match request (user is offline)"
+                        >
+                          <UserPlus className="w-4 h-4" />
+                        </button>
+                      ) : (
+                        <div
+                          className="p-1 rounded flex-shrink-0 text-gray-300 cursor-not-allowed"
+                          title="User has not declared heats yet"
+                        >
+                          <UserPlus className="w-4 h-4" />
+                        </div>
+                      )
+                    }
+                  />
+                );
+              })}
+            </div>
+          </div>
+        )}
       </div>
     </div>
   );
diff --git a/frontend/src/components/users/UserListItem.jsx b/frontend/src/components/users/UserListItem.jsx
index c8c21c6..961da1f 100644
--- a/frontend/src/components/users/UserListItem.jsx
+++ b/frontend/src/components/users/UserListItem.jsx
@@ -83,12 +83,19 @@ const UserListItem = ({
               {user.firstName} {user.lastName}
             </p>
           )}
-          {/* Heat Badges */}
+          {/* Heat Badges or No Heats indicator */}
           {showHeats && hasHeats && (
             <div className="mt-1">
               <HeatBadges heats={heats} maxVisible={3} />
             </div>
           )}
+          {showHeats && !hasHeats && (
+            <div className="mt-1">
+              <span className="inline-flex items-center px-2 py-0.5 text-xs font-medium bg-gray-200 text-gray-600 rounded">
+                No heats declared
+              </span>
+            </div>
+          )}
         </div>
       </div>
       {actionButton && (