diff --git a/CHANGELOG.md b/CHANGELOG.md
index f4bce08..85170e1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,12 @@
+# 4.0.0 (2021-11-11)
+* Refactor cart tax calculation to stop calculation events from triggering twice
+* Fix issue with tax calculation on dynamically created products and variations
+* Fix issue where in some cases fees did not use correct product tax codes during calculation
+* Fix issue where multiple products with the same product tax and exemption thresholds may cause incorrect tax
+* Update minimum WooCommerce version to 5.4
+* WooCommerce tested up to version 5.9
+* WordPress tested up to version 5.8.2
+
 # 3.3.0 (2021-09-02)
 * Fix php warning when store settings are not set
 * Update minimum WordPress version to 5.4
diff --git a/readme.txt b/readme.txt
index a3ed2a8..7fb953e 100755
--- a/readme.txt
+++ b/readme.txt
@@ -2,12 +2,12 @@
 Contributors: taxjar, tonkapark, fastdivision
 Tags: woocommerce, taxjar, tax, taxes, sales tax, tax calculation, sales tax compliance, sales tax filing
 Requires at least: 5.4
-Tested up to: 5.8
-Stable tag: 3.3.0
+Tested up to: 5.8.2
+Stable tag: 4.0.0
 License: GPLv2 or later
 URI: http://www.gnu.org/licenses/gpl-2.0.html
-WC requires at least: 5.1.0
-WC tested up to: 5.6.0
+WC requires at least: 5.4.0
+WC tested up to: 5.9.0
 
 Trusted by more than 20,000 businesses, TaxJar’s award-winning solution makes it easy to automate sales tax reporting and filing, and determine economic nexus with a single click.
 
@@ -95,6 +95,14 @@ Our plans come with filings included, with additional filings available for purc
 
 == Changelog ==
 
+= 4.0.0 (2021-11-11)
+* Refactor cart tax calculation to stop calculation events from triggering twice
+* Fix issue with tax calculation on dynamically created products and variations
+* Fix issue where in some cases fees did not use correct product tax codes during calculation
+* Fix issue where multiple products with the same product tax and exemption thresholds may cause incorrect tax
+* Update minimum WooCommerce version to 5.4
+* WooCommerce tested up to version 5.9
+
 = 3.3.0 (2021-09-02)
 * Fix php warning when store settings are not set
 * Update minimum WordPress version to 5.4
diff --git a/taxjar-woocommerce.php b/taxjar-woocommerce.php
index d58dec6..972ba3b 100755
--- a/taxjar-woocommerce.php
+++ b/taxjar-woocommerce.php
@@ -3,11 +3,11 @@
  * Plugin Name: TaxJar - Sales Tax Automation for WooCommerce
  * Plugin URI: https://www.taxjar.com/woocommerce-sales-tax-plugin/
  * Description: Save hours every month by putting your sales tax on autopilot. Automated, multi-state sales tax calculation, collection, and filing.
- * Version: 3.3.0
+ * Version: 4.0.0
  * Author: TaxJar
  * Author URI: https://www.taxjar.com
- * WC requires at least: 5.1.0
- * WC tested up to: 5.6.0
+ * WC requires at least: 5.4.0
+ * WC tested up to: 5.9.0
  * Requires PHP: 7.0
  *
  * Copyright: © 2014-2019 TaxJar. TaxJar is a trademark of TPS Unlimited, Inc.
@@ -43,8 +43,8 @@
  */
 final class WC_Taxjar {
 
-	static $version = '3.4.0';
-	public static $minimum_woocommerce_version = '5.1.0';
+	static $version = '4.0.0';
+	public static $minimum_woocommerce_version = '5.4.0';
 
 	/**
 	 * Construct the plugin.