diff --git a/packages/billing/core/package.json b/packages/billing/core/package.json
index c7825e493..433cb9eea 100644
--- a/packages/billing/core/package.json
+++ b/packages/billing/core/package.json
@@ -12,7 +12,8 @@
   "exports": {
     ".": "./src/index.ts",
     "./components/*": "./src/components/*",
-    "./schema": "./src/schema/index.ts"
+    "./schema": "./src/schema/index.ts",
+    "./types": "./src/types/index.ts"
   },
   "peerDependencies": {
     "@kit/supabase": "0.1.0",
diff --git a/packages/billing/core/src/services/billing-webhook-handler.service.ts b/packages/billing/core/src/services/billing-webhook-handler.service.ts
index ac7574a58..2a0084a97 100644
--- a/packages/billing/core/src/services/billing-webhook-handler.service.ts
+++ b/packages/billing/core/src/services/billing-webhook-handler.service.ts
@@ -1,10 +1,4 @@
-import { Database } from '@kit/supabase/database';
-
-type UpsertSubscriptionParams =
-  Database['public']['Functions']['upsert_subscription']['Args'];
-
-type UpsertOrderParams =
-  Database['public']['Functions']['upsert_order']['Args'];
+import { UpsertOrderParams, UpsertSubscriptionParams } from '../types';
 
 /**
  * @name BillingWebhookHandlerService
@@ -44,7 +38,7 @@ export abstract class BillingWebhookHandlerService {
       onPaymentFailed: (sessionId: string) => Promise<unknown>;
 
       // generic handler for any event
-      onEvent?: (event: string, data: unknown) => Promise<unknown>;
+      onEvent?: <Data>(event: string, data: Data) => Promise<unknown>;
     },
   ): Promise<unknown>;
 }
diff --git a/packages/billing/core/src/types/index.ts b/packages/billing/core/src/types/index.ts
new file mode 100644
index 000000000..a77634d90
--- /dev/null
+++ b/packages/billing/core/src/types/index.ts
@@ -0,0 +1,24 @@
+import { Database } from '@kit/supabase/database';
+
+type LineItems = Array<{
+  id: string;
+  quantity: number;
+  product_id: string;
+  variant_id: string;
+  price_amount: number;
+}>;
+
+export type UpsertSubscriptionParams =
+  Database['public']['Functions']['upsert_subscription']['Args'] & {
+    line_items: LineItems & {
+      interval: string;
+      subscription_id: string;
+      interval_count: number;
+      type: 'per_seat' | 'flat' | 'metered';
+    };
+  };
+
+export type UpsertOrderParams =
+  Database['public']['Functions']['upsert_order']['Args'] & {
+    line_items: LineItems;
+  };
diff --git a/packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler.service.ts b/packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler.service.ts
index f8e233a32..3879173b2 100644
--- a/packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler.service.ts
+++ b/packages/billing/gateway/src/server/services/billing-event-handler/billing-event-handler.service.ts
@@ -3,32 +3,13 @@ import 'server-only';
 import { SupabaseClient } from '@supabase/supabase-js';
 
 import { BillingWebhookHandlerService } from '@kit/billing';
+import {
+  UpsertOrderParams,
+  UpsertSubscriptionParams,
+} from '@kit/billing/types';
 import { getLogger } from '@kit/shared/logger';
 import { Database } from '@kit/supabase/database';
 
-type LineItems = Array<{
-  id: string;
-  quantity: number;
-  product_id: string;
-  variant_id: string;
-  price_amount: number;
-}>;
-
-type UpsertSubscriptionParams =
-  Database['public']['Functions']['upsert_subscription']['Args'] & {
-    line_items: LineItems & {
-      interval: string;
-      subscription_id: string;
-      interval_count: number;
-      type: 'per_seat' | 'flat' | 'metered';
-    };
-  };
-
-type UpsertOrderParams =
-  Database['public']['Functions']['upsert_order']['Args'] & {
-    line_items: LineItems;
-  };
-
 /**
  * @name CustomHandlersParams
  * @description Allow consumers to provide custom handlers for the billing events