diff --git a/packages/babel-preset-env/src/normalize-options.js b/packages/babel-preset-env/src/normalize-options.js
index 026ac96e83..edbaaa52e9 100644
--- a/packages/babel-preset-env/src/normalize-options.js
+++ b/packages/babel-preset-env/src/normalize-options.js
@@ -204,7 +204,7 @@ export function normalizeCoreJSOption(
   if (useBuiltIns && corejs === undefined) {
     rawVersion = 2;
     console.log(
-      "\nWe noticed you're using the `useBuiltIns` option without declaring a " +
+      "\nWARNING: We noticed you're using the `useBuiltIns` option without declaring a " +
         "core-js version. Currently, we assume version 2.x when no version " +
         "is passed. Since this default version will likely change in future " +
         "versions of Babel, we recommend explicitly setting the core-js version " +
diff --git a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-no-import/stdout.txt b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-no-import/stdout.txt
index d16a002045..e17f65ad8f 100644
--- a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-no-import/stdout.txt
+++ b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-no-import/stdout.txt
@@ -1,4 +1,4 @@
-We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
+WARNING: We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
 
 You should also be sure that the version you pass to the `corejs` option matches the version specified in your `package.json`'s `dependencies` section. If it doesn't, you need to run one of the following commands:
 
diff --git a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-shippedProposals/stdout.txt b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-shippedProposals/stdout.txt
index e338c6d932..b54f7b6358 100644
--- a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-shippedProposals/stdout.txt
+++ b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-shippedProposals/stdout.txt
@@ -1,4 +1,4 @@
-We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
+WARNING: We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
 
 You should also be sure that the version you pass to the `corejs` option matches the version specified in your `package.json`'s `dependencies` section. If it doesn't, you need to run one of the following commands:
 
diff --git a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-uglify/stdout.txt b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-uglify/stdout.txt
index 31c42932de..1c478c4eae 100644
--- a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-uglify/stdout.txt
+++ b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs-uglify/stdout.txt
@@ -1,4 +1,4 @@
-We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
+WARNING: We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
 
 You should also be sure that the version you pass to the `corejs` option matches the version specified in your `package.json`'s `dependencies` section. If it doesn't, you need to run one of the following commands:
 
diff --git a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs/stdout.txt b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs/stdout.txt
index 5d7438003c..6467473c2b 100644
--- a/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs/stdout.txt
+++ b/packages/babel-preset-env/test/debug-fixtures/entry-no-corejs/stdout.txt
@@ -1,4 +1,4 @@
-We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
+WARNING: We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
 
 You should also be sure that the version you pass to the `corejs` option matches the version specified in your `package.json`'s `dependencies` section. If it doesn't, you need to run one of the following commands:
 
diff --git a/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs-none/stdout.txt b/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs-none/stdout.txt
index 13cb1284bd..cd94fc7915 100644
--- a/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs-none/stdout.txt
+++ b/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs-none/stdout.txt
@@ -1,4 +1,4 @@
-We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
+WARNING: We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
 
 You should also be sure that the version you pass to the `corejs` option matches the version specified in your `package.json`'s `dependencies` section. If it doesn't, you need to run one of the following commands:
 
diff --git a/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs/stdout.txt b/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs/stdout.txt
index 197bbf297e..1f62218fb7 100644
--- a/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs/stdout.txt
+++ b/packages/babel-preset-env/test/debug-fixtures/usage-no-corejs/stdout.txt
@@ -1,4 +1,4 @@
-We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
+WARNING: We noticed you're using the `useBuiltIns` option without declaring a core-js version. Currently, we assume version 2.x when no version is passed. Since this default version will likely change in future versions of Babel, we recommend explicitly setting the core-js version you are using via the `corejs` option.
 
 You should also be sure that the version you pass to the `corejs` option matches the version specified in your `package.json`'s `dependencies` section. If it doesn't, you need to run one of the following commands: