diff --git a/pycbc/waveform/bank.py b/pycbc/waveform/bank.py
index 8aabb87f694..d02124d9da3 100644
--- a/pycbc/waveform/bank.py
+++ b/pycbc/waveform/bank.py
@@ -828,14 +828,17 @@ def __getitem__(self, index):
             ttotal = htilde.length_in_time
         else:
             ttotal = None
-        if hasattr(htilde, 'chirp_length'):
+        # First try to load template_duration from get_waveform_filter,
+        # if not exists, check if the template bank file contains template_duration,
+        # if none of them exists, return None 
+        if hasattr(htilde, 'chirp_length') and htilde.chirp_length is not None:
             template_duration = htilde.chirp_length
             self.table[index].template_duration = template_duration
         elif self.table[index].template_duration > 0:
-            # The template bank file contains 'template_duration'
             template_duration = self.table[index].template_duration
         else:
             template_duration = None
+            self.table[index].template_duration = None
 
         htilde = htilde.astype(self.dtype)
         htilde.f_lower = f_low