diff --git a/.changeset/brave-months-shop.md b/.changeset/brave-months-shop.md
new file mode 100644
index 0000000000..361671c21c
--- /dev/null
+++ b/.changeset/brave-months-shop.md
@@ -0,0 +1,5 @@
+---
+'@digdir/designsystemet-react': patch
+---
+
+Correctly mark dependencies as external. This ensures Accordion works when consumers have enabled tree-shaking.
diff --git a/packages/react/package.json b/packages/react/package.json
index 895b86f47d..e65c161b6a 100644
--- a/packages/react/package.json
+++ b/packages/react/package.json
@@ -56,7 +56,6 @@
     "react-dom": "^18.3.1",
     "rimraf": "^6.0.1",
     "rollup": "^4.20.0",
-    "rollup-plugin-peer-deps-external": "^2.2.4",
     "typescript": "^5.5.4"
   }
 }
diff --git a/packages/react/rollup.config.js b/packages/react/rollup.config.js
index 473aaf373c..4e700e7ff7 100644
--- a/packages/react/rollup.config.js
+++ b/packages/react/rollup.config.js
@@ -1,6 +1,26 @@
 import commonjs from '@rollup/plugin-commonjs';
 import resolve from '@rollup/plugin-node-resolve';
-import peerDepsExternal from 'rollup-plugin-peer-deps-external';
+import pkg from './package.json';
+
+// These are dependencies, but are not in our package.json
+const implicitDependencies = [
+  '@digdir/designsystemet-theme',
+  '@digdir/designsystemet-css',
+  '@digdir/design-system-tokens',
+];
+
+const dependencies = Object.keys({
+  ...implicitDependencies,
+  ...pkg.dependencies,
+  ...pkg.peerDependencies,
+});
+
+/*
+Regexes to correctly mark submodules from dependencies as being external
+*/
+const dependenciesSubmodules = dependencies.map(
+  (dep) => new RegExp(`^${dep}/`),
+);
 
 export default [
   {
@@ -21,12 +41,7 @@ export default [
         preserveModulesRoot: 'tsc-build',
       },
     ],
-    external: [
-      /@digdir\/designsystemet-theme/,
-      /@digdir\/designsystemet-css/,
-      /@digdir\/design-system-tokens/,
-      /@navikt\/aksel-icons/,
-    ],
-    plugins: [peerDepsExternal(), resolve(), commonjs()],
+    external: [...dependencies, ...dependenciesSubmodules],
+    plugins: [resolve(), commonjs()],
   },
 ];
diff --git a/yarn.lock b/yarn.lock
index 6a3bf11a61..6b4fe6baee 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2983,7 +2983,6 @@ __metadata:
     react-dom: "npm:^18.3.1"
     rimraf: "npm:^6.0.1"
     rollup: "npm:^4.20.0"
-    rollup-plugin-peer-deps-external: "npm:^2.2.4"
     typescript: "npm:^5.5.4"
   peerDependencies:
     react: ">=18.3.1"
@@ -14984,15 +14983,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"rollup-plugin-peer-deps-external@npm:^2.2.4":
-  version: 2.2.4
-  resolution: "rollup-plugin-peer-deps-external@npm:2.2.4"
-  peerDependencies:
-    rollup: "*"
-  checksum: 10/49b7b3f5ca14550146249b5fd86043bffb82a2c40750c80a1845c3b694fadde58435bae0c912ad8cb1c1ef6c1f8ad64914153793391cb13d52e2bc3aa2ac61e2
-  languageName: node
-  linkType: hard
-
 "rollup@npm:^4.13.0":
   version: 4.14.0
   resolution: "rollup@npm:4.14.0"