From 51c30e2b42ad98d25060b3772879b3e414cfec0e Mon Sep 17 00:00:00 2001
From: Matthew Phillips <matthew@matthewphillips.info>
Date: Thu, 2 Apr 2026 16:04:43 -0400
Subject: [PATCH] Skip actions server-output validation when an adapter is
 configured

---
 .changeset/actions-static-with-adapter.md |  5 +++++
 packages/astro/src/actions/integration.ts |  2 +-
 packages/astro/test/actions.test.js       | 19 +++++++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/actions-static-with-adapter.md

diff --git a/.changeset/actions-static-with-adapter.md b/.changeset/actions-static-with-adapter.md
new file mode 100644
index 000000000000..69376273c8e4
--- /dev/null
+++ b/.changeset/actions-static-with-adapter.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixes Actions failing with `ActionsWithoutServerOutputError` when using `output: 'static'` with an adapter
diff --git a/packages/astro/src/actions/integration.ts b/packages/astro/src/actions/integration.ts
index e8a5d5a002c2..562700eb55f0 100644
--- a/packages/astro/src/actions/integration.ts
+++ b/packages/astro/src/actions/integration.ts
@@ -41,7 +41,7 @@ export default function astroIntegrationActionsRouteHandler({
 				});
 			},
 			'astro:routes:resolved': ({ routes }) => {
-				if (!hasNonPrerenderedRoute(routes)) {
+				if (!settings.config.adapter && !hasNonPrerenderedRoute(routes)) {
 					const error = new AstroError(ActionsWithoutServerOutputError);
 					error.stack = undefined;
 					throw error;
diff --git a/packages/astro/test/actions.test.js b/packages/astro/test/actions.test.js
index 59af60e5faae..7438477dd512 100644
--- a/packages/astro/test/actions.test.js
+++ b/packages/astro/test/actions.test.js
@@ -476,6 +476,25 @@ describe('Astro Actions in static mode with prerender = false routes', () => {
 	});
 });
 
+it('Works with adapter and all pages prerendered', async () => {
+	const fixture = await loadFixture({
+		root: './fixtures/actions/',
+		output: 'static',
+		adapter: testAdapter(),
+	});
+	const devServer = await fixture.startDevServer();
+	const res = await fixture.fetch('/_actions/subscribe', {
+		method: 'POST',
+		headers: {
+			'Content-Type': 'application/json',
+		},
+		body: JSON.stringify({ channel: 'bholmesdev' }),
+	});
+
+	assert.equal(res.ok, true);
+	await devServer.stop();
+});
+
 it('Base path should be used', async () => {
 	const fixture = await loadFixture({
 		root: './fixtures/actions/',