diff --git a/depth_filter.py b/depth_filter.py
index a39713f..059abde 100644
--- a/depth_filter.py
+++ b/depth_filter.py
@@ -85,7 +85,7 @@ def getFormatField(sample_name, field_name):
         filter=False
         for samp in args.sample_names.split(","):
             depth = getFormatField(samp,args.site_depth_field)
-            if(depth=="NA"):
+            if(depth in ("NA", ".")):
                 if na_err:
                     print("WARNING: One or more sites lack the {} field. Those are being treated as zero and filtered".format(args.site_depth_field))
                     na_err=False