diff --git a/src/reference/openapi.yml b/src/reference/openapi.yml
index 3579ae434..9e6318da0 100644
--- a/src/reference/openapi.yml
+++ b/src/reference/openapi.yml
@@ -5398,6 +5398,33 @@ paths:
         required: true
         schema:
           type: string
+  '/dossiers/{campaign}/costs':
+    parameters:
+      - schema:
+          type: string
+        name: campaign
+        in: path
+        required: true
+    get:
+      summary: Your GET endpoint
+      tags: []
+      responses:
+        '200':
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  totalCost:
+                    type: number
+      operationId: get-dossiers-campaign-costs
+      x-stoplight:
+        id: q9l4m7dj053wk
+      security:
+        - JWT: []
+      parameters:
+        - $ref: '#/components/parameters/filterBy'
   /education:
     get:
       operationId: get-education
diff --git a/src/routes/dossiers/campaignId/costs/_get/index.spec.ts b/src/routes/dossiers/campaignId/costs/_get/index.spec.ts
new file mode 100644
index 000000000..47199cc55
--- /dev/null
+++ b/src/routes/dossiers/campaignId/costs/_get/index.spec.ts
@@ -0,0 +1,178 @@
+import app from "@src/app";
+import { tryber } from "@src/features/database";
+import request from "supertest";
+
+const campaign_1 = {
+  id: 1,
+  project_id: 1,
+  platform_id: 1,
+  start_date: "2023-01-13 10:10:10",
+  end_date: "2023-01-14 10:10:10",
+  title: "",
+  page_preview_id: 1,
+  page_manual_id: 1,
+  customer_id: 1,
+  pm_id: 1,
+  customer_title: "",
+  tokens_usage: 25,
+};
+const campaign_2 = {
+  ...campaign_1,
+  id: 2,
+  project_id: 1,
+  tokens_usage: 10,
+};
+const campaign_3 = {
+  ...campaign_1,
+  id: 3,
+  project_id: 1,
+  tokens_usage: 5,
+};
+const project = {
+  display_name: "",
+  edited_by: 1,
+};
+
+const payment_1 = {
+  id: 11,
+  tester_id: 1,
+  campaign_id: 1,
+  amount: 100.5,
+  is_paid: 1,
+  is_requested: 1,
+  work_type: "test",
+  note: "note",
+  receipt_id: -1,
+  work_type_id: 1,
+};
+
+const payment_2 = {
+  ...payment_1,
+  id: 22,
+  tester_id: 2,
+  campaign_id: 1,
+  amount: 200.75,
+  is_paid: 1,
+  is_requested: 1,
+  work_type_id: 2,
+};
+
+const payment_3 = {
+  ...payment_1,
+  id: 33,
+  tester_id: 3,
+  campaign_id: 2,
+  amount: 300.25,
+  is_paid: 1,
+  is_requested: 1,
+};
+
+describe("GET /dossiers/campaignId/costs", () => {
+  beforeAll(async () => {
+    await tryber.tables.WpAppqEvdCampaign.do().insert([
+      campaign_1,
+      campaign_2,
+      campaign_3,
+    ]);
+    await tryber.tables.WpAppqProject.do().insert([
+      {
+        ...project,
+        display_name: "Project 1",
+        id: 1,
+        customer_id: 1,
+      },
+      {
+        ...project,
+        display_name: "Project 3",
+        id: 3,
+        customer_id: 2,
+      },
+    ]);
+    await tryber.tables.WpAppqPayment.do().insert([
+      payment_1,
+      payment_2,
+      payment_3,
+    ]);
+  });
+  afterAll(async () => {
+    await tryber.tables.WpAppqCustomer.do().delete();
+  });
+
+  it("Should answer 403 if not logged in", () => {
+    return request(app).get("/dossiers/1/costs").expect(403);
+  });
+  it("Should answer 403 if logged in without permissions", async () => {
+    const response = await request(app)
+      .get("/dossiers/1/costs")
+      .set("Authorization", "Bearer tester");
+    expect(response.status).toBe(403);
+  });
+  it("Should answer 400 if campaign does not exists", async () => {
+    const response = await request(app)
+      .get("/dossiers/100/costs")
+      .set("Authorization", "Bearer tester");
+    expect(response.status).toBe(400);
+  });
+
+  it("Should answer 403 if logged as user without permissions on the campaign", async () => {
+    const response = await request(app)
+      .get("/dossiers/2/costs")
+      .set("Authorization", 'Bearer tester olp {"appq_campaign":[1]}');
+    expect(response.status).toBe(403);
+  });
+
+  it("Should answer 200 if logged as user with full access on the campaign", async () => {
+    const response = await request(app)
+      .get("/dossiers/1/costs")
+      .set("Authorization", 'Bearer tester olp {"appq_campaign":[1]}');
+    expect(response.status).toBe(200);
+  });
+
+  it("Should answer with the campaigns costs", async () => {
+    const response = await request(app)
+      .get("/dossiers/1/costs")
+      .set("Authorization", 'Bearer tester olp {"appq_campaign":[1]}');
+    expect(response.status).toBe(200);
+    expect(response.body).toEqual({
+      totalCost: payment_1.amount + payment_2.amount,
+    });
+  });
+  it("Should filterBy the costs by work_type_id", async () => {
+    const response = await request(app)
+      .get("/dossiers/1/costs?filterBy[type]=2")
+      .set("Authorization", 'Bearer tester olp {"appq_campaign":[1]}');
+    expect(response.status).toBe(200);
+    expect(response.body).toEqual({
+      totalCost: payment_2.amount,
+    });
+  });
+
+  it("Should filterBy the costs by multiple work_type_id", async () => {
+    const response = await request(app)
+      .get("/dossiers/1/costs?filterBy[type]=1,2")
+      .set("Authorization", 'Bearer tester olp {"appq_campaign":[1]}');
+    expect(response.status).toBe(200);
+    expect(response.body).toEqual({
+      totalCost: payment_1.amount + payment_2.amount,
+    });
+  });
+
+  it("Should ignore the filter if it the type is invalid", async () => {
+    const response = await request(app)
+      .get("/dossiers/1/costs?filterBy[type]=invalid")
+      .set("Authorization", 'Bearer tester olp {"appq_campaign":[1]}');
+    expect(response.status).toBe(200);
+    expect(response.body).toEqual({
+      totalCost: payment_1.amount + payment_2.amount,
+    });
+  });
+  it("Should ignore the filter if it the filter is invalid", async () => {
+    const response = await request(app)
+      .get("/dossiers/1/costs?filterBy[invalid]=1")
+      .set("Authorization", 'Bearer tester olp {"appq_campaign":[1]}');
+    expect(response.status).toBe(200);
+    expect(response.body).toEqual({
+      totalCost: payment_1.amount + payment_2.amount,
+    });
+  });
+});
diff --git a/src/routes/dossiers/campaignId/costs/_get/index.ts b/src/routes/dossiers/campaignId/costs/_get/index.ts
new file mode 100644
index 000000000..006d7329a
--- /dev/null
+++ b/src/routes/dossiers/campaignId/costs/_get/index.ts
@@ -0,0 +1,86 @@
+/** OPENAPI-CLASS : get-dossiers-campaign-costs */
+
+import OpenapiError from "@src/features/OpenapiError";
+import { tryber } from "@src/features/database";
+import CampaignRoute from "@src/features/routes/CampaignRoute";
+
+export default class RouteItem extends CampaignRoute<{
+  response: StoplightOperations["get-dossiers-campaign-costs"]["responses"]["200"]["content"]["application/json"];
+  parameters: StoplightOperations["get-dossiers-campaign-costs"]["parameters"]["path"];
+  query: StoplightOperations["get-dossiers-campaign-costs"]["parameters"]["query"];
+}> {
+  private campaignId: number;
+  private filterBy: {
+    type?: string | string[];
+  } = {};
+
+  constructor(configuration: RouteClassConfiguration) {
+    super(configuration);
+    const query = this.getQuery();
+    this.campaignId = Number(this.getParameters().campaign);
+    if (query.filterBy) {
+      this.filterBy = query.filterBy;
+    }
+  }
+
+  protected async filter() {
+    if (!(await super.filter())) return false;
+
+    if (!this.hasAccessToCampaign(this.campaignId)) {
+      this.setError(403, new OpenapiError("You are not authorized to do this"));
+      return false;
+    }
+
+    if (!(await this.campaignExists())) {
+      this.setError(403, new OpenapiError("Campaign does not exist"));
+      return false;
+    }
+
+    return true;
+  }
+
+  private async campaignExists(): Promise<boolean> {
+    const campaign = await tryber.tables.WpAppqEvdCampaign.do()
+      .select("id")
+      .where({
+        id: this.campaignId,
+      })
+      .first();
+    if (!campaign) return false;
+
+    return true;
+  }
+
+  protected async prepare(): Promise<void> {
+    const cost = await this.calculateTotalCost();
+    return this.setSuccess(200, cost);
+  }
+
+  private async calculateTotalCost() {
+    let query = tryber.tables.WpAppqPayment.do().where({
+      campaign_id: this.campaignId,
+    });
+
+    if (this.filterBy && this.filterBy.type !== undefined) {
+      const rawTypes = Array.isArray(this.filterBy.type)
+        ? this.filterBy.type
+        : [this.filterBy.type];
+
+      const types = rawTypes
+        .map((t) => Number(t))
+        .filter((t) => !Number.isNaN(t));
+
+      if (types.length > 0) {
+        query = query.whereIn("work_type_id", types);
+      }
+    }
+
+    const paymentsTotal = (await query
+      .sum("amount as totalAmount")
+      .first()) as unknown as { totalAmount: string | number | null };
+
+    return {
+      totalCost: paymentsTotal ? Number(paymentsTotal.totalAmount || 0) : 0,
+    };
+  }
+}
diff --git a/src/schema.ts b/src/schema.ts
index 8e74a7907..66f4617a9 100644
--- a/src/schema.ts
+++ b/src/schema.ts
@@ -395,6 +395,14 @@ export interface paths {
       };
     };
   };
+  "/dossiers/{campaign}/costs": {
+    get: operations["get-dossiers-campaign-costs"];
+    parameters: {
+      path: {
+        campaign: string;
+      };
+    };
+  };
   "/education": {
     /** Get all education levels */
     get: operations["get-education"];
@@ -3229,6 +3237,27 @@ export interface operations {
       };
     };
   };
+  "get-dossiers-campaign-costs": {
+    parameters: {
+      path: {
+        campaign: string;
+      };
+      query: {
+        /** Key-value Array for item filtering */
+        filterBy?: components["parameters"]["filterBy"];
+      };
+    };
+    responses: {
+      /** OK */
+      200: {
+        content: {
+          "application/json": {
+            totalCost?: number;
+          };
+        };
+      };
+    };
+  };
   /** Get all education levels */
   "get-education": {
     responses: {