diff --git a/includes/class-wc-ajax.php b/includes/class-wc-ajax.php
index 7c89d0e7ef9..440d2d707da 100644
--- a/includes/class-wc-ajax.php
+++ b/includes/class-wc-ajax.php
@@ -729,6 +729,10 @@ class WC_AJAX {
 			wc_deprecated_function( 'The woocommerce_found_customer_details filter', '2.7', 'woocommerce_found_customer_details' );
 		}
 
+		$data = $customer->get_data();
+		$data['date_created']  = $data['date_created'] ? $data['date_created']->getTimestamp() : null;
+		$data['date_modified'] = $data['date_modified'] ? $data['date_modified']->getTimestamp() : null;
+
 		$customer_data = apply_filters( 'woocommerce_ajax_get_customer_details', $customer->get_data(), $customer, $user_id );
 		wp_send_json( $customer_data );
 	}