diff --git a/layouts/_default/rss.xml b/layouts/_default/rss.xml
index 342986d..89dec2c 100644
--- a/layouts/_default/rss.xml
+++ b/layouts/_default/rss.xml
@@ -60,7 +60,7 @@
     <managingEditor>{{.}}{{ with $authorName }} ({{ . }}){{ end }}</managingEditor>{{ end }}{{ with $authorEmail }}
     <webMaster>{{ . }}{{ with $authorName }} ({{ . }}){{ end }}</webMaster>{{ end }}{{ with site.Copyright }}
     <copyright>{{ . }}</copyright>{{ end }}{{ if not .Date.IsZero }}
-    <lastBuildDate>{{ .Date.Format "Mon, 02 Jan 2006 15:04:05 -0700" | safeHTML }}</lastBuildDate>{{ end }}
+    <lastBuildDate>{{ (index $pages.ByLastmod.Reverse 0).Lastmod.Format "Mon, 02 Jan 2006 15:04:05 -0700" | safeHTML }}</lastBuildDate>{{ end }}
     {{- with .OutputFormats.Get "RSS" }}
     {{ printf "<atom:link href=%q rel=\"self\" type=%q />" .Permalink .MediaType | safeHTML }}
     {{- end }}