diff --git a/pkgs/servers/sql/postgresql/libpq.nix b/pkgs/servers/sql/postgresql/libpq.nix
index 5ea0c5113225..96c05fdf54c6 100644
--- a/pkgs/servers/sql/postgresql/libpq.nix
+++ b/pkgs/servers/sql/postgresql/libpq.nix
@@ -40,14 +40,14 @@
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "libpq";
-  version = "18.4";
+  version = "18.6";
 
   src = fetchFromGitHub {
     owner = "postgres";
     repo = "postgres";
     # rev, not tag, on purpose: see generic.nix.
-    rev = "refs/tags/REL_18_4";
-    hash = "sha256-Ac/Dqcj8vjcW3my5vsnKaMiQqTq/HPtUzckJ3SMyrfA=";
+    rev = "refs/tags/REL_18_6";
+    hash = "sha256-ySffxlG7jlNyzx++BmIN+WuaQ9TMAJt/qER9wIjd6B8=";
   };
 
   __structuredAttrs = true;