diff --git a/CHANGELOG.md b/CHANGELOG.md
index be0fcd4..4b05138 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,9 +5,9 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## [8.4.0] - 2026-09-29
 
-To be released as **8.4.0**, a minor: the additions below are backwards
+A minor release: the additions below are backwards
 compatible at runtime. One is not quite so at the type level: `HistorySpan`
 gains a required field, `finalThrough`, so code that builds a `HistorySpan`
 object by hand (a test double, say) needs to add it. Code that only reads the
diff --git a/package-lock.json b/package-lock.json
index 1978870..41597a6 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "themeparks",
-  "version": "8.3.1",
+  "version": "8.4.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "themeparks",
-      "version": "8.3.1",
+      "version": "8.4.0",
       "license": "MIT",
       "bin": {
         "themeparks-backfill": "dist/backfill-cli.js"
diff --git a/package.json b/package.json
index a46e1b8..7c8c1fc 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "themeparks",
-  "version": "8.3.1",
+  "version": "8.4.0",
   "description": "Official SDK for the ThemeParks.wiki API",
   "license": "MIT",
   "repository": "github:ThemeParks/ThemeParks_JavaScript",
diff --git a/src/client.ts b/src/client.ts
index 7f26e7e..26f76d0 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -13,7 +13,7 @@ import type { RateLimits } from './ratelimit';
 const DEFAULT_BASE_URL = 'https://api.themeparks.wiki/v1';
 /** Exported so the backfill command can announce the same version rather
  *  than carrying a second literal that drifts. test/unit/version.test.ts pins it. */
-export const PACKAGE_VERSION = '8.3.1';
+export const PACKAGE_VERSION = '8.4.0';
 export const DEFAULT_USER_AGENT = `themeparks-sdk-js/${PACKAGE_VERSION}`;
 
 export interface ThemeParksOptions {