diff --git a/packages/sns/lib/utils/snsAttributeUtils.ts b/packages/sns/lib/utils/snsAttributeUtils.ts
index 78acb84e..98b8369d 100644
--- a/packages/sns/lib/utils/snsAttributeUtils.ts
+++ b/packages/sns/lib/utils/snsAttributeUtils.ts
@@ -1,4 +1,3 @@
-import { GetCallerIdentityCommand, type STSClient } from '@aws-sdk/client-sts'
 import type { ZodSchema } from 'zod'
 
 // See https://docs.aws.amazon.com/IAM/latest/UserGuide/reference_policies_elements_version.html
@@ -62,18 +61,3 @@ export function generateFilterAttributes(
     FilterPolicyScope: 'MessageBody',
   }
 }
-
-/**
- * Manually builds the ARN of a topic based on the current AWS account and the topic name.
- * It follows the following pattern: arn:aws:sns:<region>:<account-id>:<topic-name>
- * Doc -> https://docs.aws.amazon.com/IAM/latest/UserGuide/reference-arns.html
- *
- * // TODO: add tests
- */
-export const buildTopicArn = async (client: STSClient, topicName: string) => {
-  const identityResponse = await client.send(new GetCallerIdentityCommand({}))
-  const region =
-    typeof client.config.region === 'string' ? client.config.region : await client.config.region()
-
-  return `arn:aws:sns:${region}:${identityResponse.Account}:${topicName}`
-}
diff --git a/packages/sns/lib/utils/stsUtils.spec.ts b/packages/sns/lib/utils/stsUtils.spec.ts
new file mode 100644
index 00000000..8aa0901f
--- /dev/null
+++ b/packages/sns/lib/utils/stsUtils.spec.ts
@@ -0,0 +1,20 @@
+import type { STSClient } from '@aws-sdk/client-sts'
+import { beforeAll, describe, expect, it } from 'vitest'
+import { registerDependencies } from '../../test/utils/testContext'
+import { buildTopicArn } from './stsUtils'
+
+describe('stsUtils', () => {
+  let stsClient: STSClient
+
+  beforeAll(async () => {
+    const diContainer = await registerDependencies({}, false)
+    stsClient = diContainer.cradle.stsClient
+  })
+
+  describe('buildTopicArn', () => {
+    it('build ARN for topic', async () => {
+      const topicName = 'my-test-topic'
+      await expect(buildTopicArn(stsClient, topicName)).resolves.toMatchInlineSnapshot(`"arn:aws:sns:eu-west-1:000000000000:my-test-topic"`)
+    })
+  })
+})
diff --git a/packages/sns/lib/utils/stsUtils.ts b/packages/sns/lib/utils/stsUtils.ts
new file mode 100644
index 00000000..908bda8e
--- /dev/null
+++ b/packages/sns/lib/utils/stsUtils.ts
@@ -0,0 +1,14 @@
+import { GetCallerIdentityCommand, type STSClient } from '@aws-sdk/client-sts'
+
+/**
+ * Manually builds the ARN of a topic based on the current AWS account and the topic name.
+ * It follows the following pattern: arn:aws:sns:<region>:<account-id>:<topic-name>
+ * Doc -> https://docs.aws.amazon.com/IAM/latest/UserGuide/reference-arns.html
+ */
+export const buildTopicArn = async (client: STSClient, topicName: string) => {
+  const identityResponse = await client.send(new GetCallerIdentityCommand({}))
+  const region =
+    typeof client.config.region === 'string' ? client.config.region : await client.config.region()
+
+  return `arn:aws:sns:${region}:${identityResponse.Account}:${topicName}`
+}