diff --git a/doc/_timezones.rdoc b/doc/_timezones.rdoc
index 94dbd8eeb9..e355d699b4 100644
--- a/doc/_timezones.rdoc
+++ b/doc/_timezones.rdoc
@@ -76,6 +76,9 @@ The timezone methods are:
   keyword argument +in:+, and when Time#getlocal or Time#localtime is called
   with +tz+ as the value for positional argument +zone+.
 
+  The UTC offset will be calculated as the difference between the
+  original time and the returned object as an +Integer+.
+
   Argument:: a {Time-like object}[rdoc-ref:Time@Time-Like+Objects].
   Returns:: a {Time-like object}[rdoc-ref:Time@Time-Like+Objects] in the local timezone.