diff --git a/.changeset/smart-wombats-peel.md b/.changeset/smart-wombats-peel.md
new file mode 100644
index 0000000000..6e5715b3b1
--- /dev/null
+++ b/.changeset/smart-wombats-peel.md
@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fix --mode flag for builds
diff --git a/packages/astro/src/cli/index.ts b/packages/astro/src/cli/index.ts
index 7cdff0305d..3af54bc3ef 100644
--- a/packages/astro/src/cli/index.ts
+++ b/packages/astro/src/cli/index.ts
@@ -218,7 +218,13 @@ async function runCommand(cmd: string, flags: yargs.Arguments) {
 		case 'build': {
 			const { default: build } = await import('../core/build/index.js');
 
-			return await build(settings, { flags, logging, telemetry, teardownCompiler: true });
+			return await build(settings, {
+				flags,
+				logging,
+				telemetry,
+				teardownCompiler: true,
+				mode: flags.mode,
+			});
 		}
 
 		case 'check': {