diff --git a/app/challenges-platform/index.ts b/app/challenges-platform/index.ts
index ff4dd23..1bf1e39 100644
--- a/app/challenges-platform/index.ts
+++ b/app/challenges-platform/index.ts
@@ -3,6 +3,7 @@ export {
   ParticipantsService,
   ReviewsService,
   SubmissionService,
+  AccesibleChallengesService,
 } from "./services";
 import { Transformer } from "./models";
 import { transformers } from "../../config/challenges-platform/transformers";
diff --git a/test/challenges-platform/factories/accessible-challenge-factory.ts b/test/challenges-platform/factories/accessible-challenge-factory.ts
new file mode 100644
index 0000000..3c7d146
--- /dev/null
+++ b/test/challenges-platform/factories/accessible-challenge-factory.ts
@@ -0,0 +1,32 @@
+import { challengeFactory } from "./challenge-factory";
+import { participantFactory } from "./participant-factory";
+import {
+  Challenge,
+  Participant,
+} from "../../../app/challenges-platform/models";
+import { AccesibleChallengesService } from "../../../app/challenges-platform";
+import { db } from "../../../db";
+import { accessibleChallenges } from "../../../db/schema";
+
+export const accessibleChallengeFactory = async ({
+    challenge,
+    participant,
+  }: {
+    challenge?: Challenge;
+    participant?: Participant;
+  } = {}): Promise<Number> => {
+    const c = challenge || (await challengeFactory());
+    const p = participant || (await participantFactory());
+
+    const insertResult = await db
+    .insert(accessibleChallenges)
+    .values({
+      challengeId: c.id,
+      participantId: p.id,
+    })
+    .returning();
+  
+    const result = await AccesibleChallengesService.count(c, p);
+    if (!result.ok) fail("Expected result to be Ok");
+    return result.val;
+  };
\ No newline at end of file
diff --git a/test/challenges-platform/services/accessible-challenges-service.test.ts b/test/challenges-platform/services/accessible-challenges-service.test.ts
new file mode 100644
index 0000000..4f819eb
--- /dev/null
+++ b/test/challenges-platform/services/accessible-challenges-service.test.ts
@@ -0,0 +1,36 @@
+import { challengeFactory } from "../factories/challenge-factory";
+import { participantFactory } from "../factories/participant-factory";
+import { accessibleChallengeFactory } from "../factories/accessible-challenge-factory";
+import { AccesibleChallengesService } from "../../../app/challenges-platform";
+
+describe("AccessibleChallengesService", () => {
+  describe("count", () => {
+    describe("when the challenge is not accessible", () => {
+      it("returns 0", async () => {
+        const challenge = await challengeFactory();
+        const participant = await participantFactory();
+
+        const result = await AccesibleChallengesService.count(challenge, participant);
+
+        if (!result.ok) fail("Expected result to be Ok");
+        expect(result.val).toBe(0);
+      });
+    });
+    describe("when the challenge is accessible", () => {
+      it("returns 1", async () => {
+        const challenge = await challengeFactory();
+        const participant = await participantFactory();
+
+        const insert = await accessibleChallengeFactory({
+            challenge,
+            participant
+        });
+
+        const result = await AccesibleChallengesService.count(challenge, participant);
+
+        if (!result.ok) fail("Expected result to be Ok");
+        expect(result.val).toBe(1);
+      });
+    });
+  })
+});
\ No newline at end of file