diff --git a/plugins/aggregators/histogram/README.md b/plugins/aggregators/histogram/README.md
index 5fd56f1fb..aad2eb431 100644
--- a/plugins/aggregators/histogram/README.md
+++ b/plugins/aggregators/histogram/README.md
@@ -44,6 +44,10 @@ of the algorithm which is implemented in the Prometheus
   ## Defaults to true.
   cumulative = true
 
+  ## Expiration interval for each histogram. The histogram will be expired if
+  ## there are no changes in any buckets for this time interval. 0 == no expiration.
+  # expiration_interval = "0m"
+
   ## Example config that aggregates all fields of the metric.
   # [[aggregators.histogram.config]]
   #   ## Right borders of buckets (with +Inf implicitly added).