diff --git a/modules/promotion/commerce_promotion.install b/modules/promotion/commerce_promotion.install
index 56f127fc..9ff16ff3 100644
--- a/modules/promotion/commerce_promotion.install
+++ b/modules/promotion/commerce_promotion.install
@@ -160,3 +160,11 @@ function commerce_promotion_update_8205() {
   $entity_definition_update->installFieldStorageDefinition('usage_limit_customer', 'commerce_promotion', 'commerce_promotion', $storage_definition);
   $entity_definition_update->installFieldStorageDefinition('usage_limit_customer', 'commerce_promotion_coupon', 'commerce_promotion', $storage_definition);
 }
+
+/**
+ * Force block_rebuild() to run for updated 'stores' field.
+ */
+function commerce_promotion_update_8206() {
+  // An empty update flushes caches, forcing block_rebuild() to run.
+  ;
+}
diff --git a/modules/promotion/src/Entity/Promotion.php b/modules/promotion/src/Entity/Promotion.php
index db405605..cb150dd9 100644
--- a/modules/promotion/src/Entity/Promotion.php
+++ b/modules/promotion/src/Entity/Promotion.php
@@ -483,7 +483,7 @@ class Promotion extends CommerceContentEntityBase implements PromotionInterface
     if (!in_array($order->bundle(), $this->getOrderTypeIds())) {
       return FALSE;
     }
-    if (!in_array($order->getStoreId(), $this->getStoreIds())) {
+    if (!empty($this->getStoreIds()) && !in_array($order->getStoreId(), $this->getStoreIds())) {
       return FALSE;
     }
     $date = $order->getCalculationDate();
@@ -680,9 +680,8 @@ class Promotion extends CommerceContentEntityBase implements PromotionInterface
 
     $fields['stores'] = BaseFieldDefinition::create('entity_reference')
       ->setLabel(t('Stores'))
-      ->setDescription(t('The stores for which the promotion is valid.'))
+      ->setDescription(t('Limit promotion availability to selected stores.'))
       ->setCardinality(BaseFieldDefinition::CARDINALITY_UNLIMITED)
-      ->setRequired(TRUE)
       ->setSetting('target_type', 'commerce_store')
       ->setSetting('handler', 'default')
       ->setDisplayOptions('form', [
diff --git a/modules/promotion/src/PromotionStorage.php b/modules/promotion/src/PromotionStorage.php
index c559992b..4d63c0c2 100644
--- a/modules/promotion/src/PromotionStorage.php
+++ b/modules/promotion/src/PromotionStorage.php
@@ -98,12 +98,15 @@ class PromotionStorage extends CommerceContentEntityStorage implements Promotion
     $or_condition = $query->orConditionGroup()
       ->condition('end_date', $date, '>')
       ->notExists('end_date');
+    $store_condition = $query->orConditionGroup()
+      ->notExists('stores')
+      ->condition('stores', [$order->getStoreId()], 'IN');
     $query
-      ->condition('stores', [$order->getStoreId()], 'IN')
       ->condition('order_types', [$order->bundle()], 'IN')
       ->condition('start_date', $date, '<=')
       ->condition('status', TRUE)
-      ->condition($or_condition);
+      ->condition($or_condition)
+      ->condition($store_condition);
     if ($offer_ids) {
       $query->condition('offer.target_plugin_id', $offer_ids, 'IN');
     }
diff --git a/modules/promotion/tests/src/Kernel/Entity/CouponTest.php b/modules/promotion/tests/src/Kernel/Entity/CouponTest.php
index 82cb4882..1397cc66 100644
--- a/modules/promotion/tests/src/Kernel/Entity/CouponTest.php
+++ b/modules/promotion/tests/src/Kernel/Entity/CouponTest.php
@@ -149,4 +149,54 @@ class CouponTest extends OrderKernelTestBase {
     $this->assertFalse($coupon->available($order));
   }
 
+  /**
+   * @covers ::available
+   */
+  public function testAvailabilityAllStores() {
+    // Test availability for promotions available in all stores
+    $order_item = OrderItem::create([
+      'type' => 'test',
+      'quantity' => 1,
+      'unit_price' => new Price('12.00', 'USD'),
+    ]);
+    $order_item->save();
+    $order = Order::create([
+      'type' => 'default',
+      'state' => 'draft',
+      'mail' => 'test@example.com',
+      'ip_address' => '127.0.0.1',
+      'order_number' => '6',
+      'store_id' => $this->store,
+      'uid' => $this->createUser(),
+      'order_items' => [$order_item],
+    ]);
+    $order->setRefreshState(Order::REFRESH_SKIP);
+    $order->save();
+
+    $promotion = Promotion::create([
+      'order_types' => ['default'],
+      'stores' => [],
+      'usage_limit' => 1,
+      'start_date' => '2017-01-01',
+      'status' => TRUE,
+    ]);
+    $promotion->save();
+
+    $coupon = Coupon::create([
+      'promotion_id' => $promotion->id(),
+      'code' => 'coupon_code',
+      'usage_limit' => 1,
+      'status' => TRUE,
+    ]);
+    $coupon->save();
+    $this->assertTrue($coupon->available($order));
+
+    $coupon->setEnabled(FALSE);
+    $this->assertFalse($coupon->available($order));
+    $coupon->setEnabled(TRUE);
+
+    \Drupal::service('commerce_promotion.usage')->register($order, $promotion, $coupon);
+    $this->assertFalse($coupon->available($order));
+  }
+
 }
diff --git a/modules/promotion/tests/src/Kernel/PromotionAvailabilityTest.php b/modules/promotion/tests/src/Kernel/PromotionAvailabilityTest.php
index 48219500..0806e962 100644
--- a/modules/promotion/tests/src/Kernel/PromotionAvailabilityTest.php
+++ b/modules/promotion/tests/src/Kernel/PromotionAvailabilityTest.php
@@ -94,6 +94,33 @@ class PromotionAvailabilityTest extends OrderKernelTestBase {
     $promotion->setStoreIds([$this->store->id()]);
   }
 
+  /**
+   * Test availability for promotions available in all stores.
+   */
+  public function testAvailabilityAllStores() {
+    $promotion = Promotion::create([
+      'order_types' => ['default'],
+      'stores' => [],
+      'usage_limit' => 2,
+      'start_date' => '2019-01-01T00:00:00',
+      'status' => TRUE,
+    ]);
+    $promotion->save();
+    $this->assertTrue($promotion->available($this->order));
+
+    $promotion->setEnabled(FALSE);
+    $this->assertFalse($promotion->available($this->order));
+    $promotion->setEnabled(TRUE);
+
+    $promotion->setOrderTypeIds(['test']);
+    $this->assertFalse($promotion->available($this->order));
+    $promotion->setOrderTypeIds(['default']);
+
+    $promotion->setStoreIds(['90']);
+    $this->assertFalse($promotion->available($this->order));
+    $promotion->setStoreIds([$this->store->id()]);
+  }
+
   /**
    * Tests the start date logic.
    */
diff --git a/modules/promotion/tests/src/Kernel/PromotionStorageTest.php b/modules/promotion/tests/src/Kernel/PromotionStorageTest.php
index 4aa33d34..1b43a174 100644
--- a/modules/promotion/tests/src/Kernel/PromotionStorageTest.php
+++ b/modules/promotion/tests/src/Kernel/PromotionStorageTest.php
@@ -186,13 +186,30 @@ class PromotionStorageTest extends OrderKernelTestBase {
       'status' => TRUE,
     ]);
     $promotion6->save();
+    // Past start date, enabled. No end time. All stores.
+    $promotion7 = Promotion::create([
+      'name' => 'Promotion 7',
+      'order_types' => [$this->orderType],
+      'start_date' => '2014-01-01T00:00:00',
+      'status' => TRUE,
+    ]);
+    $this->assertEquals(SAVED_NEW, $promotion7->save());
+    // Past start date, enabled. No end time. Different store.
+    $promotion8 = Promotion::create([
+      'name' => 'Promotion 8',
+      'order_types' => [$this->orderType],
+      'stores' => [5],
+      'start_date' => '2014-01-01T00:00:00',
+      'status' => TRUE,
+    ]);
+    $this->assertEquals(SAVED_NEW, $promotion8->save());
 
     // Confirm that the promotions were filtered by date and status,
     // and sorted by weight.
     $promotions = $this->promotionStorage->loadAvailable($this->order);
-    $this->assertCount(3, $promotions);
+    $this->assertCount(4, $promotions);
     $this->assertEquals([
-      $promotion5->id(), $promotion1->id(), $promotion2->id(),
+      $promotion5->id(), $promotion1->id(), $promotion2->id(), $promotion7->id()
     ], array_keys($promotions));
 
     // Test filtering by offer ID.