diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8ab2b2308a..fbd70e66df 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 ## (UNRELEASED)
 
+IMPROVEMENTS:
+
+* agent: Blocking queries on service-specific health and catalog endpoints now return a per-service `X-Consul-Index` improving watch performance on very busy clusters. [[GH-3890](https://github.com/hashicorp/consul/issues/3890)]
+
 BUG FIXES:
 
 * agent: Fixed an issue where the coordinate update endpoint was not correctly parsing the ACL token. [[GH-3892](https://github.com/hashicorp/consul/issues/3892)]