diff --git a/.travis.yml b/.travis.yml
index 8d70e05..55f8745 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,7 @@ install:
 script:
   - npm run test3 # The pretest hook runs a build
   - npm run test4
+  - npm run test5
 deploy:
   provider: npm
   skip_cleanup: true
@@ -13,4 +14,4 @@ deploy:
   api_key: "$NPM_API_KEY"
   on:
     branch: deploy
-    tags: true
\ No newline at end of file
+    tags: true
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 9a19e27..61a55ff 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -9,4 +9,4 @@ There is one source file, `src/ConfigWebpackPlugin.js`. It is written in ES6 and
 
 Notes on Webpack versions
 -------------------------
-This project should support Webpack versions `3.x` and `4.x`. Two commands, `npm run test3` and `npm run test4` install both respective versions and test them. Travis CI is set up to build and test both versions.
+This project should support Webpack versions `3.x`, `4.x` and `5.x`. Three commands, `npm run test3`, `npm run test4` and `npm run test5` install respective versions and test them. Travis CI is set up to build and test all versions.
diff --git a/README.md b/README.md
index 55a73c8..6f328d2 100644
--- a/README.md
+++ b/README.md
@@ -50,7 +50,7 @@ console.log(CONFIG.walruses[3].name);
 
 All of `node-config`'s features, including deployment- and instance-specific files, local files, and environment variables should work with `node-config-webpack`. `node-config-webpack` bundles your config on the machine that builds it. That means if you bundle on a development machine and deploy on a production machine, you'll get the development config.
 
-`config-webpack` is tested with Webpack versions `3.x` and `4.x`.
+`config-webpack` is tested with Webpack versions `3.x`, `4.x` and `5.x`.
 
 Configuring
 -----------
diff --git a/package.json b/package.json
index f93e39c..890ce6e 100644
--- a/package.json
+++ b/package.json
@@ -8,6 +8,7 @@
     "test": "mocha --require babel-register",
     "test3": "npm install webpack@3.x && npm run test",
     "test4": "npm install webpack@4.x && npm run test",
+    "test5": "npm install webpack@5.x && npm run test",
     "pretest": "npm run build"
   },
   "repository": {
@@ -37,6 +38,6 @@
   },
   "peerDependencies": {
     "config": "^1.30.0 || ^2.0.0 || ^3.0.0",
-    "webpack": "^1.0.0 || ^2.0.0 || ^3.0.0 || ^4.0.0"
+    "webpack": "^1.0.0 || ^2.0.0 || ^3.0.0 || ^4.0.0 || ^5.0.0"
   }
 }