diff --git a/src/main.ts b/src/main.ts
index 0b6ae6d..4f4076e 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -96,7 +96,7 @@ export async function run(): Promise<void> {
   try {
     // Get action inputs
     const image = getInput('image'); // Image ie gcr.io/...
-    const service = getInput('service'); // Service name
+    let service = getInput('service'); // Service name
     const job = getInput('job'); // Job name
     const metadata = getInput('metadata'); // YAML file
     const projectId = getInput('project_id');
@@ -156,6 +156,19 @@ export async function run(): Promise<void> {
       const contents = await readFile(metadata, 'utf8');
       const parsed = parseYAML(contents);
 
+      // Extract service name from metadata template
+      const name = parsed?.metadata?.name;
+      if (!name) {
+        throw new Error(`${metadata} is missing 'metadata.name'`);
+      }
+      if (service && service != name) {
+        throw new Error(
+          `service name in ${metadata} ("${name}") does not match GitHub ` +
+            `Actions service input ("${service}")`,
+        );
+      }
+      service = name;
+
       const kind = parsed?.kind;
       if (kind === 'Service') {
         deployCmd = ['run', 'services', 'replace', metadata];
diff --git a/tests/unit/main.test.ts b/tests/unit/main.test.ts
index 4b2f2a0..a0cac83 100644
--- a/tests/unit/main.test.ts
+++ b/tests/unit/main.test.ts
@@ -337,6 +337,31 @@ test('#run', { concurrency: true }, async (suite) => {
     assertMembers(args, ['services', 'replace']);
   });
 
+  await suite.test('errors if metadata is given and the service names do not match', async (t) => {
+    defaultMocks(t.mock, {
+      metadata: 'tests/fixtures/service.yaml',
+      service: 'not-a-match',
+    });
+
+    await assert.rejects(
+      async () => {
+        await run();
+      },
+      { message: /does not match/ },
+    );
+  });
+
+  await suite.test('does not error if metadata is given and the service names match', async (t) => {
+    defaultMocks(t.mock, {
+      metadata: 'tests/fixtures/service.yaml',
+      service: 'run-full-yaml',
+    });
+
+    await assert.doesNotReject(async () => {
+      await run();
+    });
+  });
+
   await suite.test('sets job metadata if given', async (t) => {
     const mocks = defaultMocks(t.mock, {
       metadata: 'tests/fixtures/job.yaml',