diff --git a/packages/app/src/plugins/cost-insights/ExampleCostInsightsClient.ts b/packages/app/src/plugins/cost-insights/ExampleCostInsightsClient.ts
index c01092dc51..e1ef77c537 100644
--- a/packages/app/src/plugins/cost-insights/ExampleCostInsightsClient.ts
+++ b/packages/app/src/plugins/cost-insights/ExampleCostInsightsClient.ts
@@ -23,6 +23,7 @@ import {
   Project,
   ProductCost,
   Group,
+  Maybe,
 } from '@backstage/plugin-cost-insights';
 
 export class ExampleCostInsightsClient implements CostInsightsApi {
@@ -122,9 +123,38 @@ export class ExampleCostInsightsClient implements CostInsightsApi {
     product: string,
     group: string,
     duration: Duration,
+    project: Maybe<string>,
   ): Promise<ProductCost> {
+    const projectProductInsights = await this.request(
+      { product, group, duration, project },
+      {
+        aggregation: [80_000, 110_000],
+        change: {
+          ratio: 0.375,
+          amount: 30_000,
+        },
+        entities: [
+          {
+            id: null, // entities with null ids will be appear as "Unlabeled" in product panels
+            aggregation: [45_000, 50_000],
+          },
+          {
+            id: 'entity-a',
+            aggregation: [15_000, 20_000],
+          },
+          {
+            id: 'entity-b',
+            aggregation: [20_000, 30_000],
+          },
+          {
+            id: 'entity-e',
+            aggregation: [0, 10_000],
+          },
+        ],
+      },
+    );
     const productInsights: ProductCost = await this.request(
-      { product, group, duration },
+      { product, group, duration, project },
       {
         aggregation: [200_000, 250_000],
         change: {
@@ -172,7 +202,7 @@ export class ExampleCostInsightsClient implements CostInsightsApi {
       },
     );
 
-    return productInsights;
+    return project ? projectProductInsights : productInsights;
   }
 
   async getAlerts(group: string): Promise<Alert[]> {
diff --git a/plugins/cost-insights/src/api/CostInsightsApi.ts b/plugins/cost-insights/src/api/CostInsightsApi.ts
index b7628e2f9e..bdf673b7d1 100644
--- a/plugins/cost-insights/src/api/CostInsightsApi.ts
+++ b/plugins/cost-insights/src/api/CostInsightsApi.ts
@@ -15,7 +15,15 @@
  */
 
 import { createApiRef } from '@backstage/core';
-import { Alert, Cost, Duration, Group, Project, ProductCost } from '../types';
+import {
+  Alert,
+  Cost,
+  Duration,
+  Group,
+  Project,
+  ProductCost,
+  Maybe,
+} from '../types';
 
 export type CostInsightsApi = {
   /**
@@ -87,6 +95,9 @@ export type CostInsightsApi = {
    * in this product. The type of entity depends on the product - it may be deployed services,
    * storage buckets, managed database instances, etc.
    *
+   * If project is supplied, this should only return product costs for the given billing entity
+   * (project in GCP).
+   *
    * The time period is supplied as a Duration rather than intervals, since this is always expected
    * to return data for two bucketed time period (e.g. month vs month, or quarter vs quarter).
    *
@@ -94,11 +105,13 @@ export type CostInsightsApi = {
    * @param group
    * @param duration A time duration, such as P1M. See the Duration type for a detailed explanation
    *    of how the durations are interpreted in Cost Insights.
+   * @param project (optional) The project id from getGroupProjects or query parameters
    */
   getProductInsights(
     product: string,
     group: string,
     duration: Duration,
+    project: Maybe<string>,
   ): Promise<ProductCost>;
 
   /**