diff --git a/src/@dates/setdiff.m b/src/@dates/setdiff.m
index 1abe6943bf626a60446edff3cf6d59a81c289715..db62cacd4235ea7ff6451d9a9650a6b7cdd53fa2 100644
--- a/src/@dates/setdiff.m
+++ b/src/@dates/setdiff.m
@@ -34,6 +34,11 @@ if ~isequal(o.freq,p.freq)
     error('dates;setdiff','All input arguments must have common frequency!')
 end
 
+if isempty(p)
+    q = copy(o);
+    return
+end
+
 if o==p
     q = dates(o.freq);
     return