diff --git a/.changeset/small-gorillas-remain.md b/.changeset/small-gorillas-remain.md
new file mode 100644
index 0000000000..03d12139de
--- /dev/null
+++ b/.changeset/small-gorillas-remain.md
@@ -0,0 +1,5 @@
+---
+'@aws-amplify/backend-cli': patch
+---
+
+throw user error when sandbox identifier validation fails
diff --git a/package-lock.json b/package-lock.json
index d1f0b2600b..06b7cca03b 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -24670,7 +24670,7 @@
     },
     "packages/ai-constructs": {
       "name": "@aws-amplify/ai-constructs",
-      "version": "0.1.1",
+      "version": "0.1.2",
       "license": "Apache-2.0",
       "dependencies": {
         "@aws-amplify/plugin-types": "^1.0.1",
@@ -24869,7 +24869,7 @@
     },
     "packages/backend-secret": {
       "name": "@aws-amplify/backend-secret",
-      "version": "1.1.0",
+      "version": "1.1.1",
       "license": "Apache-2.0",
       "dependencies": {
         "@aws-amplify/platform-core": "^1.0.5",
@@ -25511,11 +25511,11 @@
     },
     "packages/sandbox": {
       "name": "@aws-amplify/sandbox",
-      "version": "1.2.0",
+      "version": "1.2.1",
       "license": "Apache-2.0",
       "dependencies": {
         "@aws-amplify/backend-deployer": "^1.1.0",
-        "@aws-amplify/backend-secret": "^1.1.0",
+        "@aws-amplify/backend-secret": "^1.1.1",
         "@aws-amplify/cli-core": "^1.1.2",
         "@aws-amplify/client-config": "^1.1.3",
         "@aws-amplify/deployed-backend-client": "^1.3.0",
diff --git a/packages/cli/src/commands/sandbox/sandbox_command.test.ts b/packages/cli/src/commands/sandbox/sandbox_command.test.ts
index a240f33d59..7b653d877c 100644
--- a/packages/cli/src/commands/sandbox/sandbox_command.test.ts
+++ b/packages/cli/src/commands/sandbox/sandbox_command.test.ts
@@ -21,6 +21,7 @@ import { createSandboxSecretCommand } from './sandbox-secret/sandbox_secret_comm
 import { ClientConfigGeneratorAdapter } from '../../client-config/client_config_generator_adapter.js';
 import { CommandMiddleware } from '../../command_middleware.js';
 import { PackageManagerController } from '@aws-amplify/plugin-types';
+import { AmplifyError } from '@aws-amplify/platform-core';
 
 mock.method(fsp, 'mkdir', () => Promise.resolve());
 
@@ -121,6 +122,24 @@ void describe('sandbox command', () => {
     );
   });
 
+  void it('throws AmplifyUserError if invalid identifier is provided', async () => {
+    const invalidIdentifier = 'invalid@';
+    await assert.rejects(
+      () =>
+        commandRunner.runCommand(`sandbox --identifier ${invalidIdentifier}`), // invalid identifier
+      (err: TestCommandError) => {
+        assert.ok(err.error instanceof AmplifyError);
+        assert.strictEqual(
+          err.error.message,
+          'Invalid --identifier provided: invalid@'
+        );
+        assert.strictEqual(err.error.name, 'InvalidCommandInputError');
+        return true;
+      }
+    );
+    assert.equal(sandboxStartMock.mock.callCount(), 0);
+  });
+
   void it('shows available options in help output', async () => {
     const output = await commandRunner.runCommand('sandbox --help');
     assert.match(output, /--identifier/);
diff --git a/packages/cli/src/commands/sandbox/sandbox_command.ts b/packages/cli/src/commands/sandbox/sandbox_command.ts
index 1da7519f6a..356d0a8eb6 100644
--- a/packages/cli/src/commands/sandbox/sandbox_command.ts
+++ b/packages/cli/src/commands/sandbox/sandbox_command.ts
@@ -21,6 +21,7 @@ import { CommandMiddleware } from '../../command_middleware.js';
 import { SandboxCommandGlobalOptions } from './option_types.js';
 import { ArgumentsKebabCase } from '../../kebab_case.js';
 import { PackageManagerController } from '@aws-amplify/plugin-types';
+import { AmplifyUserError } from '@aws-amplify/platform-core';
 
 export type SandboxCommandOptionsKebabCase = ArgumentsKebabCase<
   {
@@ -254,9 +255,11 @@ export class SandboxCommand
           if (argv.identifier) {
             const identifierRegex = /^[a-zA-Z0-9-]{1,15}$/;
             if (!argv.identifier.match(identifierRegex)) {
-              throw new Error(
-                `--identifier should match [a-zA-Z0-9-] and be less than 15 characters.`
-              );
+              throw new AmplifyUserError('InvalidCommandInputError', {
+                message: `Invalid --identifier provided: ${argv.identifier}`,
+                resolution:
+                  'Use an identifier that matches [a-zA-Z0-9-] and is less than 15 characters.',
+              });
             }
           }
           return true;
diff --git a/scripts/components/api-changes-validator/test-resources/test-projects/with-breaks/class-break-constructor/expected-error-message.txt b/scripts/components/api-changes-validator/test-resources/test-projects/with-breaks/class-break-constructor/expected-error-message.txt
index 5dce9746df..a20179f04b 100644
--- a/scripts/components/api-changes-validator/test-resources/test-projects/with-breaks/class-break-constructor/expected-error-message.txt
+++ b/scripts/components/api-changes-validator/test-resources/test-projects/with-breaks/class-break-constructor/expected-error-message.txt
@@ -5,5 +5,6 @@ index.ts(23,18): error TS2558: Expected 1 type arguments, but got 2.
 index.ts(24,18): error TS2558: Expected 1 type arguments, but got 2.
 index.ts(36,34): error TS2554: Expected 1 arguments, but got 2.
 index.ts(42,34): error TS2345: Argument of type 'string | undefined' is not assignable to parameter of type 'number | undefined'.
+  Type 'string' is not assignable to type 'number'.
 index.ts(47,26): error TS2558: Expected 1 type arguments, but got 2.
 index.ts(48,26): error TS2558: Expected 1 type arguments, but got 2.