diff --git a/includes/class-wc-coupon.php b/includes/class-wc-coupon.php
index 2b8dcaea823..d31a546cac1 100644
--- a/includes/class-wc-coupon.php
+++ b/includes/class-wc-coupon.php
@@ -37,7 +37,7 @@ class WC_Coupon extends WC_Legacy_Coupon {
 		'excluded_product_ids'        => array(),
 		'usage_limit'                 => 0,
 		'usage_limit_per_user'        => 0,
-		'limit_usage_to_x_items'      => 0,
+		'limit_usage_to_x_items'      => null,
 		'free_shipping'               => false,
 		'product_categories'          => array(),
 		'excluded_product_categories' => array(),
@@ -262,7 +262,7 @@ class WC_Coupon extends WC_Legacy_Coupon {
 	 * Usage limited to certain amount of items
 	 * @since  3.0.0
 	 * @param  string $context
-	 * @return integer
+	 * @return integer|null
 	 */
 	public function get_limit_usage_to_x_items( $context = 'view' ) {
 		return $this->get_prop( 'limit_usage_to_x_items', $context );
@@ -388,11 +388,12 @@ class WC_Coupon extends WC_Legacy_Coupon {
 		// Handle the limit_usage_to_x_items option
 		if ( ! $this->is_type( array( 'fixed_cart' ) ) ) {
 			if ( $discounting_amount ) {
-				if ( ! $this->get_limit_usage_to_x_items() ) {
+				if ( null === $this->get_limit_usage_to_x_items() ) {
 					$limit_usage_qty = $cart_item_qty;
 				} else {
 					$limit_usage_qty = min( $this->get_limit_usage_to_x_items(), $cart_item_qty );
-					$this->set_limit_usage_to_x_items( max( 0, $this->get_limit_usage_to_x_items() - $limit_usage_qty ) );
+
+					$this->set_limit_usage_to_x_items( max( 0, ( $this->get_limit_usage_to_x_items() - $limit_usage_qty ) ) );
 				}
 				if ( $single ) {
 					$discount = ( $discount * $limit_usage_qty ) / $cart_item_qty;
@@ -557,11 +558,11 @@ class WC_Coupon extends WC_Legacy_Coupon {
 	/**
 	 * Set usage limit to x number of items.
 	 * @since  3.0.0
-	 * @param  int $limit_usage_to_x_items
+	 * @param  int|null $limit_usage_to_x_items
 	 * @throws WC_Data_Exception
 	 */
 	public function set_limit_usage_to_x_items( $limit_usage_to_x_items ) {
-		$this->set_prop( 'limit_usage_to_x_items', absint( $limit_usage_to_x_items ) );
+		$this->set_prop( 'limit_usage_to_x_items', is_null( $limit_usage_to_x_items ) ? null : absint( $limit_usage_to_x_items ) );
 	}
 
 	/**
@@ -1027,7 +1028,7 @@ class WC_Coupon extends WC_Legacy_Coupon {
 		}
 
 		$valid        = false;
-		$product_cats = wc_get_product_cat_ids( $product->get_id() );
+		$product_cats = wc_get_product_cat_ids( $product->is_type( 'variation' ) ? $product->get_parent_id() : $product->get_id() );
 		$product_ids  = array( $product->get_id(), $product->get_parent_id() );
 
 		// Specific products get the discount
diff --git a/includes/data-stores/class-wc-coupon-data-store-cpt.php b/includes/data-stores/class-wc-coupon-data-store-cpt.php
index 226c12d8b27..ab38afa44bd 100644
--- a/includes/data-stores/class-wc-coupon-data-store-cpt.php
+++ b/includes/data-stores/class-wc-coupon-data-store-cpt.php
@@ -105,7 +105,7 @@ class WC_Coupon_Data_Store_CPT extends WC_Data_Store_WP implements WC_Coupon_Dat
 			'excluded_product_ids'        => array_filter( (array) explode( ',', get_post_meta( $coupon_id, 'exclude_product_ids', true ) ) ),
 			'usage_limit'                 => get_post_meta( $coupon_id, 'usage_limit', true ),
 			'usage_limit_per_user'        => get_post_meta( $coupon_id, 'usage_limit_per_user', true ),
-			'limit_usage_to_x_items'      => get_post_meta( $coupon_id, 'limit_usage_to_x_items', true ),
+			'limit_usage_to_x_items'      => 0 < get_post_meta( $coupon_id, 'limit_usage_to_x_items', true ) ? get_post_meta( $coupon_id, 'limit_usage_to_x_items', true ) : null,
 			'free_shipping'               => 'yes' === get_post_meta( $coupon_id, 'free_shipping', true ),
 			'product_categories'          => array_filter( (array) get_post_meta( $coupon_id, 'product_categories', true ) ),
 			'excluded_product_categories' => array_filter( (array) get_post_meta( $coupon_id, 'exclude_product_categories', true ) ),