diff --git a/openapi/components/schemas/Invoice.yaml b/openapi/components/schemas/Invoice.yaml
index ecb0c377c8..c6ac6943c2 100644
--- a/openapi/components/schemas/Invoice.yaml
+++ b/openapi/components/schemas/Invoice.yaml
@@ -16,6 +16,13 @@ properties:
     readOnly: true
     type: integer
     x-basic: true
+  orderId:
+    description: ID of the order.
+    readOnly: true
+    example: ord_01GYJPRKHBD6ZYHH897QCJMBS4
+    type:
+      - 'string'
+      - 'null'
   subscriptionId:
     type: string
     description: |-
diff --git a/openapi/components/schemas/StorefrontInvoice.yaml b/openapi/components/schemas/StorefrontInvoice.yaml
index 8537206420..f4753ed157 100644
--- a/openapi/components/schemas/StorefrontInvoice.yaml
+++ b/openapi/components/schemas/StorefrontInvoice.yaml
@@ -12,6 +12,13 @@ properties:
     readOnly: true
     type: integer
     x-basic: true
+  orderId:
+    description: ID of the order.
+    readOnly: true
+    example: ord_01GYJPRKHBD6ZYHH897QCJMBS4
+    type:
+      - 'string'
+      - 'null'
   subscriptionId:
     type: string
     description: |-