diff --git a/pkgs/servers/sql/postgresql/default.nix b/pkgs/servers/sql/postgresql/default.nix
index 307c9f5f4e32..7398b68f23b7 100644
--- a/pkgs/servers/sql/postgresql/default.nix
+++ b/pkgs/servers/sql/postgresql/default.nix
@@ -307,10 +307,12 @@ let
   };
 
   mkPackages = self: {
+    # TODO: remove ahead of 23.11 branchoff
+    # "PostgreSQL 11 will stop receiving fixes on November 9, 2023"
     postgresql_11 = self.callPackage generic {
-      version = "11.20";
+      version = "11.21";
       psqlSchema = "11.1"; # should be 11, but changing it is invasive
-      hash = "sha256-PXyIgvZKfphTSgRCV9/uerrXelt9oSUI2F1yK5i1rM4=";
+      hash = "sha256-B7CDdHHV3XeyUWazRxjzuhCBa2rWHmkeb8VHzz/P+FA=";
       this = self.postgresql_11;
       thisAttr = "postgresql_11";
       inherit self;