diff --git a/src/execution/IncrementalPublisher.ts b/src/execution/IncrementalPublisher.ts
index 83d2bf6b285..4b197181527 100644
--- a/src/execution/IncrementalPublisher.ts
+++ b/src/execution/IncrementalPublisher.ts
@@ -100,7 +100,7 @@ export interface IncrementalDeferResult<
 > {
   errors?: ReadonlyArray<GraphQLError>;
   data: TData;
-  id?: string;
+  id: string;
   subPath?: ReadonlyArray<string | number>;
   extensions?: TExtensions;
 }
@@ -111,7 +111,7 @@ export interface FormattedIncrementalDeferResult<
 > {
   errors?: ReadonlyArray<GraphQLFormattedError>;
   data: TData;
-  id?: string;
+  id: string;
   subPath?: ReadonlyArray<string | number>;
   extensions?: TExtensions;
 }
@@ -122,7 +122,7 @@ export interface IncrementalStreamResult<
 > {
   errors?: ReadonlyArray<GraphQLError>;
   items: TData;
-  id?: string;
+  id: string;
   subPath?: ReadonlyArray<string | number>;
   extensions?: TExtensions;
 }
@@ -133,7 +133,7 @@ export interface FormattedIncrementalStreamResult<
 > {
   errors?: ReadonlyArray<GraphQLFormattedError>;
   items: TData;
-  id?: string;
+  id: string;
   subPath?: ReadonlyArray<string | number>;
   extensions?: TExtensions;
 }