diff --git a/src/compiler/config/test/validate-config.spec.ts b/src/compiler/config/test/validate-config.spec.ts
index 6a99b384bca..f60f233b18f 100644
--- a/src/compiler/config/test/validate-config.spec.ts
+++ b/src/compiler/config/test/validate-config.spec.ts
@@ -401,4 +401,25 @@ describe('validation', () => {
       expect(config.sourceMap).toBe(false);
     });
   });
+
+  describe('buildDist', () => {
+    it.each([true, false])('should set the field based on the config flag (%p)', (flag) => {
+      userConfig.flags = { esm: flag };
+      const { config } = validateConfig(userConfig);
+      expect(config.buildDist).toBe(flag);
+    });
+
+    it.each([true, false])('should fallback to !devMode', (devMode) => {
+      userConfig.devMode = devMode;
+      const { config } = validateConfig(userConfig);
+      expect(config.buildDist).toBe(!devMode);
+    });
+
+    it.each([true, false])('should fallback to buildEs5 in devMode', (buildEs5) => {
+      userConfig.devMode = true;
+      userConfig.buildEs5 = buildEs5;
+      const { config } = validateConfig(userConfig);
+      expect(config.buildDist).toBe(config.buildEs5);
+    });
+  });
 });
diff --git a/src/compiler/config/validate-config.ts b/src/compiler/config/validate-config.ts
index 65920ace748..4631e5ccd47 100644
--- a/src/compiler/config/validate-config.ts
+++ b/src/compiler/config/validate-config.ts
@@ -61,7 +61,7 @@ export const validateConfig = (
   setBooleanConfig(config, 'sourceMap', null, typeof config.sourceMap === 'undefined' ? false : config.sourceMap);
   setBooleanConfig(config, 'watch', 'watch', false);
   setBooleanConfig(config, 'buildDocs', 'docs', !config.devMode);
-  setBooleanConfig(config, 'buildDist', null, !config.devMode || config.buildEs5);
+  setBooleanConfig(config, 'buildDist', 'esm', !config.devMode || config.buildEs5);
   setBooleanConfig(config, 'profile', 'profile', config.devMode);
   setBooleanConfig(config, 'writeLog', 'log', false);
   setBooleanConfig(config, 'buildAppCore', null, true);
diff --git a/src/declarations/stencil-public-compiler.ts b/src/declarations/stencil-public-compiler.ts
index 18c0672471e..ab369f29016 100644
--- a/src/declarations/stencil-public-compiler.ts
+++ b/src/declarations/stencil-public-compiler.ts
@@ -568,6 +568,7 @@ export interface ConfigFlags {
   e2e?: boolean;
   emulate?: string;
   es5?: boolean;
+  esm?: boolean;
   headless?: boolean;
   help?: boolean;
   log?: boolean;