diff --git a/includes/abstracts/abstract-wc-order.php b/includes/abstracts/abstract-wc-order.php
index e07153da6e7..31942a57d35 100644
--- a/includes/abstracts/abstract-wc-order.php
+++ b/includes/abstracts/abstract-wc-order.php
@@ -10,6 +10,8 @@
  * @package     WooCommerce\Classes
  */
 
+use Automattic\WooCommerce\Proxies\LegacyProxy;
+use Automattic\WooCommerce\Utilities\ArrayUtil;
 use Automattic\WooCommerce\Utilities\NumberUtil;
 
 defined( 'ABSPATH' ) || exit;
@@ -1361,14 +1363,23 @@ abstract class WC_Abstract_Order extends WC_Abstract_Legacy_Order {
 	 */
 	public function add_product( $product, $qty = 1, $args = array() ) {
 		if ( $product ) {
+			$order = ArrayUtil::get_value_or_default( $args, 'order' );
+			$total = wc_get_price_excluding_tax(
+				$product,
+				array(
+					'qty'   => $qty,
+					'order' => $order,
+				)
+			);
+
 			$default_args = array(
 				'name'         => $product->get_name(),
 				'tax_class'    => $product->get_tax_class(),
 				'product_id'   => $product->is_type( 'variation' ) ? $product->get_parent_id() : $product->get_id(),
 				'variation_id' => $product->is_type( 'variation' ) ? $product->get_id() : 0,
 				'variation'    => $product->is_type( 'variation' ) ? $product->get_attributes() : array(),
-				'subtotal'     => wc_get_price_excluding_tax( $product, array( 'qty' => $qty ) ),
-				'total'        => wc_get_price_excluding_tax( $product, array( 'qty' => $qty ) ),
+				'subtotal'     => $total,
+				'total'        => $total,
 				'quantity'     => $qty,
 			);
 		} else {
@@ -1392,7 +1403,7 @@ abstract class WC_Abstract_Order extends WC_Abstract_Legacy_Order {
 			}
 		}
 
-		$item = new WC_Order_Item_Product();
+		$item = wc_get_container()->get( LegacyProxy::class )->get_instance_of( WC_Order_Item_Product::class );
 		$item->set_props( $args );
 		$item->set_backorder_meta();
 		$item->set_order_id( $this->get_id() );
diff --git a/includes/class-wc-ajax.php b/includes/class-wc-ajax.php
index 23ad973b9f2..e4b124301f6 100644
--- a/includes/class-wc-ajax.php
+++ b/includes/class-wc-ajax.php
@@ -955,7 +955,7 @@ class WC_AJAX {
 					/* translators: %s: error message */
 					throw new Exception( sprintf( __( 'Error: %s', 'woocommerce' ), $validation_error->get_error_message() ) );
 				}
-				$item_id                 = $order->add_product( $product, $qty );
+				$item_id                 = $order->add_product( $product, $qty, array( 'order' => $order ) );
 				$item                    = apply_filters( 'woocommerce_ajax_order_item', $order->get_item( $item_id ), $item_id, $order, $product );
 				$added_items[ $item_id ] = $item;
 				$order_notes[ $item_id ] = $product->get_formatted_name();
diff --git a/includes/wc-product-functions.php b/includes/wc-product-functions.php
index e09b503d582..902dceede73 100644
--- a/includes/wc-product-functions.php
+++ b/includes/wc-product-functions.php
@@ -9,6 +9,8 @@
  */
 
 use Automattic\Jetpack\Constants;
+use Automattic\WooCommerce\Proxies\LegacyProxy;
+use Automattic\WooCommerce\Utilities\ArrayUtil;
 use Automattic\WooCommerce\Utilities\NumberUtil;
 
 defined( 'ABSPATH' ) || exit;
@@ -1081,7 +1083,9 @@ function wc_get_price_excluding_tax( $product, $args = array() ) {
 	$line_price = $price * $qty;
 
 	if ( $product->is_taxable() && wc_prices_include_tax() ) {
-		$tax_rates      = WC_Tax::get_rates( $product->get_tax_class() );
+		$order          = ArrayUtil::get_value_or_default( $args, 'order' );
+		$customer       = $order ? wc_get_container()->get( LegacyProxy::class )->get_instance_of( WC_Customer::class, $order->get_customer_id() ) : null;
+		$tax_rates      = WC_Tax::get_rates( $product->get_tax_class(), $customer );
 		$base_tax_rates = WC_Tax::get_base_tax_rates( $product->get_tax_class( 'unfiltered' ) );
 		$remove_taxes   = apply_filters( 'woocommerce_adjust_non_base_location_prices', true ) ? WC_Tax::calc_tax( $line_price, $base_tax_rates, true ) : WC_Tax::calc_tax( $line_price, $tax_rates, true );
 		$return_price   = $line_price - array_sum( $remove_taxes ); // Unrounded since we're dealing with tax inclusive prices. Matches logic in cart-totals class. @see adjust_non_base_location_price.
diff --git a/tests/legacy/mockable-functions.php b/tests/legacy/mockable-functions.php
index 3fbdeab5672..974619882e0 100644
--- a/tests/legacy/mockable-functions.php
+++ b/tests/legacy/mockable-functions.php
@@ -12,6 +12,8 @@ return array(
 	'get_bloginfo',
 	'get_woocommerce_currencies',
 	'get_woocommerce_currency_symbol',
+	'wc_get_price_excluding_tax',
 	'wc_get_shipping_method_count',
+	'wc_prices_include_tax',
 	'wc_site_is_https',
 );
diff --git a/tests/php/includes/abstracts/class-wc-abstract-order-test.php b/tests/php/includes/abstracts/class-wc-abstract-order-test.php
index a26f5cc565c..be35d13756a 100644
--- a/tests/php/includes/abstracts/class-wc-abstract-order-test.php
+++ b/tests/php/includes/abstracts/class-wc-abstract-order-test.php
@@ -5,6 +5,8 @@
  * @package WooCommerce\Tests\Abstracts
  */
 
+use Automattic\WooCommerce\Testing\Tools\CodeHacking\Hacks\FunctionsMockerHack;
+
 /**
  * Class WC_Abstract_Order.
  */
@@ -100,12 +102,12 @@ class WC_Abstract_Order_Test extends WC_Unit_Test_Case {
 		update_option( 'woocommerce_default_country', 'IN:AP' );
 
 		$tax_rate = array(
-			'tax_rate_country'  => 'IN',
-			'tax_rate_state'    => '',
-			'tax_rate'          => '25.0000',
-			'tax_rate_name'     => 'tax',
-			'tax_rate_order'    => '1',
-			'tax_rate_class'    => '',
+			'tax_rate_country' => 'IN',
+			'tax_rate_state'   => '',
+			'tax_rate'         => '25.0000',
+			'tax_rate_name'    => 'tax',
+			'tax_rate_order'   => '1',
+			'tax_rate_class'   => '',
 		);
 		WC_Tax::_insert_tax_rate( $tax_rate );
 
@@ -137,4 +139,49 @@ class WC_Abstract_Order_Test extends WC_Unit_Test_Case {
 		$this->assertEquals( 2, $order->get_discount_tax() );
 	}
 
+	/**
+	 * @testdox 'add_product' passes the order supplied in '$args' to 'wc_get_price_excluding_tax', and uses the obtained price as total and subtotal for the line item.
+	 */
+	public function test_add_product_passes_order_to_wc_get_price_excluding_tax() {
+		$product_passed_to_get_price = false;
+		$args_passed_to_get_price    = false;
+
+		FunctionsMockerHack::add_function_mocks(
+			array(
+				'wc_get_price_excluding_tax' => function( $product, $args = array() ) use ( &$product_passed_to_get_price, &$args_passed_to_get_price ) {
+						$product_passed_to_get_price = $product;
+						$args_passed_to_get_price    = $args;
+
+						return 1234;
+				},
+			)
+		);
+
+		//phpcs:disable Squiz.Commenting
+		$order_item = new class() extends WC_Order_Item_Product {
+			public $passed_props;
+
+			public function set_props( $args, $context = 'set' ) {
+				$this->passed_props = $args;
+			}
+		};
+		//phpcs:enable Squiz.Commenting
+
+		$this->register_legacy_proxy_class_mocks(
+			array( 'WC_Order_Item_Product' => $order_item )
+		);
+
+		$product = WC_Helper_Product::create_simple_product();
+		$product->set_regular_price( 100 );
+		$product->save();
+
+		$order = wc_create_order();
+
+		$order->add_product( $product, 1, array( 'order' => $order ) );
+
+		$this->assertSame( $product, $product_passed_to_get_price );
+		$this->assertSame( $order, $args_passed_to_get_price['order'] );
+		$this->assertEquals( 1234, $order_item->passed_props['total'] );
+		$this->assertEquals( 1234, $order_item->passed_props['subtotal'] );
+	}
 }
diff --git a/tests/php/includes/wc-product-functions-test.php b/tests/php/includes/wc-product-functions-test.php
new file mode 100644
index 00000000000..26fedee2c6a
--- /dev/null
+++ b/tests/php/includes/wc-product-functions-test.php
@@ -0,0 +1,97 @@
+<?php
+/**
+ * Unit tests for wc-product-functions.php.
+ *
+ * @package WooCommerce\Tests\Functions\Stock
+ */
+
+use Automattic\WooCommerce\Testing\Tools\CodeHacking\Hacks\FunctionsMockerHack;
+use Automattic\WooCommerce\Testing\Tools\CodeHacking\Hacks\StaticMockerHack;
+
+/**
+ * Class WC_Stock_Functions_Tests.
+ */
+class WC_Product_Functions_Tests extends \WC_Unit_Test_Case {
+
+	/**
+	 * @testdox If 'wc_get_price_excluding_tax' gets an order as argument, it passes the order customer to 'WC_Tax::get_rates'.
+	 *
+	 * @testWith [true]
+	 *           [false]
+	 *
+	 * @param bool $pass_order Whether an order is passed to 'wc_get_price_excluding_tax' or not.
+	 */
+	public function test_wc_get_price_excluding_tax_passes_order_customer_to_get_rates_if_order_is_available( $pass_order ) {
+		$customer_passed_to_get_rates                  = false;
+		$customer_id_passed_to_wc_customer_constructor = false;
+
+		FunctionsMockerHack::add_function_mocks(
+			array(
+				'wc_prices_include_tax' => '__return_true',
+			)
+		);
+
+		StaticMockerHack::add_method_mocks(
+			array(
+				'WC_Tax' =>
+				array(
+					'get_rates'          => function( $tax_class, $customer ) use ( &$customer_passed_to_get_rates ) {
+						$customer_passed_to_get_rates = $customer;
+					},
+					'get_base_tax_rates' => function( $tax_class ) {
+						return 0;
+					},
+					'calc_tax'           => function( $price, $rates, $price_includes_tax = false, $deprecated = false ) {
+						return array( 0 );
+					},
+				),
+			)
+		);
+
+		// phpcs:disable Squiz.Commenting.FunctionComment.Missing
+
+		$product = new class() extends WC_Product {
+			public function get_price( $context = 'view' ) {
+				return 0;
+			}
+
+			public function is_taxable() {
+				return true;
+			}
+
+			public function get_tax_class( $context = 'view' ) {
+				return '';
+			}
+		};
+
+		$customer = new stdClass();
+		$this->register_legacy_proxy_class_mocks(
+			array(
+				'WC_Customer' => function( $customer_id ) use ( &$customer_id_passed_to_wc_customer_constructor, $customer ) {
+					$customer_id_passed_to_wc_customer_constructor = $customer_id;
+					return $customer;
+				},
+			)
+		);
+
+		if ( $pass_order ) {
+			$order = new class() {
+				public function get_customer_id() {
+					return 1;
+				}
+			};
+
+			wc_get_price_excluding_tax( $product, array( 'order' => $order ) );
+
+			$this->assertEquals( $order->get_customer_id(), $customer_id_passed_to_wc_customer_constructor );
+			$this->assertSame( $customer, $customer_passed_to_get_rates );
+		} else {
+			wc_get_price_excluding_tax( $product );
+
+			$this->assertFalse( $customer_id_passed_to_wc_customer_constructor );
+			$this->assertNull( $customer_passed_to_get_rates );
+		}
+
+		// phpcs:enable Squiz.Commenting.FunctionComment.Missing
+	}
+}