diff --git a/mercurial/branchmap.py b/mercurial/branchmap.py
--- a/mercurial/branchmap.py
+++ b/mercurial/branchmap.py
@@ -211,10 +211,13 @@
         Raise KeyError for unknown branch.'''
         return self._branchtip(self[branch])[0]
 
+    def iteropen(self, nodes):
+        return (n for n in nodes if n not in self._closednodes)
+
     def branchheads(self, branch, closed=False):
         heads = self[branch]
         if not closed:
-            heads = [h for h in heads if h not in self._closednodes]
+            heads = list(self.iteropen(heads))
         return heads
 
     def iterbranches(self):
diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -1077,7 +1077,10 @@
     allheads = set(repo.heads())
     branches = []
     for tag, heads, tip, isclosed in repo.branchmap().iterbranches():
-        isactive = not isclosed and bool(set(heads) & allheads)
+        isactive = False
+        if not isclosed:
+            openheads = set(repo.branchmap().iteropen(heads))
+            isactive = bool(openheads & allheads)
         branches.append((tag, repo[tip], isactive, not isclosed))
     branches.sort(key=lambda i: (i[2], i[1].rev(), i[0], i[3]),
                   reverse=True)