diff --git a/packages/react-scripts/template-typescript/src/serviceWorker.ts b/packages/react-scripts/template-typescript/src/serviceWorker.ts
index 01eea8797c8..d5f0275a77d 100644
--- a/packages/react-scripts/template-typescript/src/serviceWorker.ts
+++ b/packages/react-scripts/template-typescript/src/serviceWorker.ts
@@ -108,7 +108,9 @@ function registerValidSW(swUrl: string, config?: Config) {
 
 function checkValidServiceWorker(swUrl: string, config?: Config) {
   // Check if the service worker can be found. If it can't reload the page.
-  fetch(swUrl)
+  fetch(swUrl, {
+    headers: { 'Service-Worker': 'script' }
+  })
     .then(response => {
       // Ensure service worker exists, and that we really are getting a JS file.
       const contentType = response.headers.get('content-type');
diff --git a/packages/react-scripts/template/src/serviceWorker.js b/packages/react-scripts/template/src/serviceWorker.js
index ceeed83fce8..8703ddb7ecb 100644
--- a/packages/react-scripts/template/src/serviceWorker.js
+++ b/packages/react-scripts/template/src/serviceWorker.js
@@ -100,7 +100,9 @@ function registerValidSW(swUrl, config) {
 
 function checkValidServiceWorker(swUrl, config) {
   // Check if the service worker can be found. If it can't reload the page.
-  fetch(swUrl)
+  fetch(swUrl, {
+    headers: { 'Service-Worker': 'script' }
+  })
     .then(response => {
       // Ensure service worker exists, and that we really are getting a JS file.
       const contentType = response.headers.get('content-type');