diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2ad946a582b..d80992d3af8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@
 - Fixed a “This password does not use the Bcrypt algorithm” error that could occur when logging in with a user whose password was set in an earlier version of Craft.
 - Fixed a “File name is not a string” error that could occur when an error was encountered when rendering a string template. ([#19122](https://github.com/craftcms/cms/pull/19122))
 - Fixed a bug where parsed site names would get saved to the project config. ([#19123](https://github.com/craftcms/cms/issues/19123))
+- Fixed several issues that occurred when Craft was configured with a custom (or no) `cpTrigger`. ([#19127](https://github.com/craftcms/cms/pull/19127))
 
 ## 6.0.0-alpha.8 - 2026-06-17
 
diff --git a/packages/craftcms-cp/src/utilities/api/actionClient.ts b/packages/craftcms-cp/src/utilities/api/actionClient.ts
index 4969ff9b1a4..6cac50742ce 100644
--- a/packages/craftcms-cp/src/utilities/api/actionClient.ts
+++ b/packages/craftcms-cp/src/utilities/api/actionClient.ts
@@ -1,11 +1,13 @@
 import axios, {type RawAxiosRequestHeaders} from 'axios';
 import {Csrf} from '@src/services/Csrf';
+import {ConfigService} from '@src/services/Config';
 
 /**
- * @TODO
+ * Builds an action URL using the runtime-configured action base
+ * (`Url::actionUrl()`), so the CP trigger isn't hard-coded to `/admin`.
  */
 export function getActionUrl(action: string = '') {
-  return `/admin/actions/${action}`;
+  return ConfigService.getInstance().getActionUrl(action);
 }
 
 /**
@@ -27,13 +29,15 @@ export function actionHeaders(): RawAxiosRequestHeaders {
   return headers;
 }
 
-export const actionClient = axios.create({
-  baseURL: getActionUrl(),
-});
+export const actionClient = axios.create();
 
 const csrf = new Csrf();
 
 actionClient.interceptors.request.use(async (config) => {
+  // Resolve the base URL lazily so it reflects the runtime CP trigger. Config
+  // isn't guaranteed to be initialized when this module is first imported.
+  config.baseURL = getActionUrl();
+
   // Set X-Requested-With header
   config.headers.set('X-Requested-With', 'XMLHttpRequest');
 
diff --git a/resources/js/bootstrap/cp.ts b/resources/js/bootstrap/cp.ts
index 60275f799cb..503c6f9b595 100644
--- a/resources/js/bootstrap/cp.ts
+++ b/resources/js/bootstrap/cp.ts
@@ -15,6 +15,7 @@ import AssetIndexes from '@/modules/utilities/components/asset-indexes/AssetInde
 import SystemMessages from '@/modules/utilities/components/system-messages/SystemMessages.vue';
 import DeprecationErrorsToolbar from '@/modules/utilities/components/deprecation-errors/DeprecationErrorsToolbar.vue';
 import {setTranslations} from '@craftcms/cp/utilities/translate.ts.mjs';
+import {setUrlDefaults} from '@/wayfinder';
 
 let bootedCallbacks: Array<(instance: any) => void> = [];
 let bootingCallbacks: Array<(instance: any) => void> = [];
@@ -23,6 +24,14 @@ let bootingCallbacks: Array<(instance: any) => void> = [];
 const config = ConfigService.getInstance();
 const queue = QueueService.getInstance();
 
+function routeSegment(value: unknown): string {
+  if (value === null || value === undefined) {
+    return '';
+  }
+
+  return value.toString().replace(/^\/+|\/+$/g, '');
+}
+
 // Create our object
 const Cp = {
   initialConfig: {} as Record<string, any>,
@@ -53,6 +62,12 @@ const Cp = {
 
   init() {
     config.initialize(this.initialConfig);
+
+    setUrlDefaults(() => ({
+      cpTrigger: routeSegment(config.get('cpTrigger')),
+      actionTrigger: routeSegment(config.get('actionTrigger')),
+    }));
+
     queue.initialize({
       runAutomatically: config.get('runQueueAutomatically', true),
       enabled: true,
diff --git a/resources/js/common/components/CurrentUser.vue b/resources/js/common/components/CurrentUser.vue
index 30c21fdc165..184c14f52c6 100644
--- a/resources/js/common/components/CurrentUser.vue
+++ b/resources/js/common/components/CurrentUser.vue
@@ -24,7 +24,9 @@
 </script>
 
 <template>
-  <craft-action-item :href="UsersController.edit['/admin/myaccount']().url">
+  <craft-action-item
+    :href="UsersController.edit['/{cpTrigger?}/myaccount']().url"
+  >
     <div class="flex items-center gap-3">
       <UserThumbnail size="md" />
       <div>
diff --git a/resources/js/common/components/UserMenu.vue b/resources/js/common/components/UserMenu.vue
index 84f674f6c0e..54b26567a1b 100644
--- a/resources/js/common/components/UserMenu.vue
+++ b/resources/js/common/components/UserMenu.vue
@@ -22,11 +22,13 @@
       },
       {type: 'hr' as const},
       {
-        href: UsersController.edit['/admin/myaccount']().url,
+        href: UsersController.edit['/{cpTrigger?}/myaccount']().url,
         label: t('Profile'),
       },
       {
-        href: PermissionsController.index['/admin/myaccount/permissions']().url,
+        href: PermissionsController.index[
+          '/{cpTrigger?}/myaccount/permissions'
+        ]().url,
         label: t('Permissions'),
       },
       {
diff --git a/resources/js/common/composables/useCraftData.ts b/resources/js/common/composables/useCraftData.ts
index d1895c4b62d..c32db8c24c7 100644
--- a/resources/js/common/composables/useCraftData.ts
+++ b/resources/js/common/composables/useCraftData.ts
@@ -30,7 +30,7 @@ export interface CraftData {
   allowAdminChanges: boolean;
   currentUser: CpUser | null;
   general: {
-    cpTrigger: string;
+    cpTrigger: string | null;
     actionTrigger: string | null;
     csrfTokenName: string | null;
     cpLogoUrl: string | null;
diff --git a/resources/js/components/form/EntryTypeSelect.vue b/resources/js/components/form/EntryTypeSelect.vue
index 3369f9fc430..a579199b24b 100644
--- a/resources/js/components/form/EntryTypeSelect.vue
+++ b/resources/js/components/form/EntryTypeSelect.vue
@@ -154,7 +154,7 @@
       </div>
     </craft-action-menu>
     <a
-      :href="create['/admin/settings/entry-types/new']().url"
+      :href="create['/{cpTrigger?}/settings/entry-types/new']().url"
       class=""
       v-if="!readOnly"
     >
diff --git a/resources/js/modules/entry-types/components/CreateEntryTypeButton.vue b/resources/js/modules/entry-types/components/CreateEntryTypeButton.vue
index faeb1337004..7eb9b006f03 100644
--- a/resources/js/modules/entry-types/components/CreateEntryTypeButton.vue
+++ b/resources/js/modules/entry-types/components/CreateEntryTypeButton.vue
@@ -11,7 +11,7 @@
 
   function createSlideout() {
     const slideout = new Craft.CpScreenSlideout(
-      create['/admin/settings/entry-types/new']().url
+      create['/{cpTrigger?}/settings/entry-types/new']().url
     );
 
     slideout.on('submit', () => {
diff --git a/resources/js/modules/install/components/InstallingScreen.vue b/resources/js/modules/install/components/InstallingScreen.vue
index 694a04bf818..f16fccbf7e2 100644
--- a/resources/js/modules/install/components/InstallingScreen.vue
+++ b/resources/js/modules/install/components/InstallingScreen.vue
@@ -1,7 +1,7 @@
 <script setup lang="ts">
   import {t} from '@craftcms/cp';
   import {onMounted} from 'vue';
-  import {usePost} from '@/common/composables/useFetch';
+  import {useActionClient} from '@/common/composables/useFetch';
   import {usePage} from '@inertiajs/vue3';
   import Pane from '@/common/components/Pane.vue';
 
@@ -17,7 +17,7 @@
     isSuccess,
     isLoading,
     isError,
-  } = usePost('/admin/actions/install/install', {
+  } = useActionClient('install/install', {
     onSuccess: () => {
       setTimeout(() => {
         window.location.href = pageProps.postCpLoginRedirect as string;
diff --git a/resources/js/modules/plugin-manager/components/PluginLinks.vue b/resources/js/modules/plugin-manager/components/PluginLinks.vue
index 80e2a490c59..754f77b0f10 100644
--- a/resources/js/modules/plugin-manager/components/PluginLinks.vue
+++ b/resources/js/modules/plugin-manager/components/PluginLinks.vue
@@ -39,7 +39,7 @@
     ) {
       links.push({
         icon: 'gear',
-        href: editSettings(props.plugin.handle).url,
+        href: editSettings({handle: props.plugin.handle}).url,
         text: 'Settings',
       });
     }
diff --git a/resources/js/modules/sites/components/DeleteSiteModal.vue b/resources/js/modules/sites/components/DeleteSiteModal.vue
index 8f232a0d16f..9feabcabfe3 100644
--- a/resources/js/modules/sites/components/DeleteSiteModal.vue
+++ b/resources/js/modules/sites/components/DeleteSiteModal.vue
@@ -41,7 +41,7 @@
   }
 
   function deleteSite() {
-    form.clearErrors().delete(destroy(props.site.id).url, {
+    form.clearErrors().delete(destroy({site: props.site.id}).url, {
       onSuccess: () => {
         emit('close');
         form.reset();
diff --git a/resources/js/modules/updater/components/Update.vue b/resources/js/modules/updater/components/Update.vue
index e794150ee15..2b5a3969931 100644
--- a/resources/js/modules/updater/components/Update.vue
+++ b/resources/js/modules/updater/components/Update.vue
@@ -107,7 +107,11 @@
           <!-- Update button -->
           <Form
             v-else
-            :action="UpdaterController.index['/admin/actions/updater']()"
+            :action="
+              UpdaterController.index[
+                '/{cpTrigger?}/{actionTrigger?}/updater'
+              ]()
+            "
             method="post"
             v-slot="{processing}"
           >
diff --git a/resources/js/modules/updater/components/Updates.vue b/resources/js/modules/updater/components/Updates.vue
index 3838005da73..0ca7290ee6a 100644
--- a/resources/js/modules/updater/components/Updates.vue
+++ b/resources/js/modules/updater/components/Updates.vue
@@ -181,7 +181,7 @@
     });
 
     router.post(
-      UpdaterController.index['/admin/actions/updater'](),
+      UpdaterController.index['/{cpTrigger?}/{actionTrigger?}/updater'](),
       {
         return: 'utilities/updates',
         install,
diff --git a/resources/js/modules/updater/composables/useUpdater.ts b/resources/js/modules/updater/composables/useUpdater.ts
index 9b4416d2ddd..cdf5c7156b2 100644
--- a/resources/js/modules/updater/composables/useUpdater.ts
+++ b/resources/js/modules/updater/composables/useUpdater.ts
@@ -1,6 +1,7 @@
 import {computed, type ComputedRef, type Ref, ref} from 'vue';
 import {t} from '@craftcms/cp';
 import axios from 'axios';
+import {useHelpers} from '@/common/composables/useCraftData';
 
 /**
  * State returned from updater API endpoints
@@ -47,6 +48,7 @@ export function useUpdater(
   actionPrefix: string,
   initialState: UpdaterState
 ): UseUpdaterReturn {
+  const {getActionUrl} = useHelpers();
   const state = ref<UpdaterState>({...initialState});
   const isLoading = ref(false);
 
@@ -62,7 +64,7 @@ export function useUpdater(
 
     try {
       response = await axios.post(
-        `/admin/actions/${actionPrefix}/${action}`,
+        getActionUrl(`${actionPrefix}/${action}`),
         {data: state.value.data},
         {
           headers: {
@@ -157,7 +159,7 @@ export function useUpdater(
     // Try to disable maintenance mode
     axios
       .post(
-        `/admin/actions/${actionPrefix}/finish`,
+        getActionUrl(`${actionPrefix}/finish`),
         {data: state.value.data},
         {
           headers: {
diff --git a/resources/js/pages/graphql/Schemas.vue b/resources/js/pages/graphql/Schemas.vue
index b42108af030..98c948f55ce 100644
--- a/resources/js/pages/graphql/Schemas.vue
+++ b/resources/js/pages/graphql/Schemas.vue
@@ -37,7 +37,7 @@
         })
       )
     ) {
-      router.delete(destroy(schema.id));
+      router.delete(destroy({schemaId: schema.id}));
     }
   }
 
@@ -48,8 +48,8 @@
         columnHelper.link('name', {
           props: ({row}) => ({
             href: row.original.isPublic
-              ? editPublic()
-              : edit(row.original.id).url,
+              ? editPublic().url
+              : edit({schemaId: row.original.id}).url,
             inertia: false,
           }),
           header: t('Name'),
diff --git a/resources/js/pages/graphql/Tokens.vue b/resources/js/pages/graphql/Tokens.vue
index 9d1c8de9d29..81a50a5c082 100644
--- a/resources/js/pages/graphql/Tokens.vue
+++ b/resources/js/pages/graphql/Tokens.vue
@@ -44,7 +44,7 @@
         })
       )
     ) {
-      router.delete(destroy(token.id));
+      router.delete(destroy({tokenId: token.id}));
     }
   }
 
@@ -54,7 +54,10 @@
       return [
         columnHelper.link('name', {
           header: t('Name'),
-          props: ({row}) => ({href: edit(row.original.id).url, inertia: false}),
+          props: ({row}) => ({
+            href: edit({tokenId: row.original.id}).url,
+            inertia: false,
+          }),
         }),
         columnHelper.date('lastUsed', {
           header: t('Last Used'),
diff --git a/resources/js/pages/settings/EntryTypes.vue b/resources/js/pages/settings/EntryTypes.vue
index 448e2a8e997..93d735479bd 100644
--- a/resources/js/pages/settings/EntryTypes.vue
+++ b/resources/js/pages/settings/EntryTypes.vue
@@ -49,7 +49,7 @@
         )
       )
     ) {
-      router.delete(destroy(entryType.id));
+      router.delete(destroy({entryType: entryType.id}));
     }
   }
 
@@ -93,9 +93,12 @@
     initialState: props.pagination,
     onChange: ({query}) => {
       router.visit(
-        index({
-          query,
-        }),
+        index(
+          {},
+          {
+            query,
+          }
+        ),
         {
           only: ['data', 'pagination'],
           preserveScroll: true,
@@ -108,9 +111,12 @@
     initialState: props.sort,
     onChange: ({query}) => {
       router.visit(
-        index({
-          query,
-        }),
+        index(
+          {},
+          {
+            query,
+          }
+        ),
         {
           only: ['data', 'sort'],
           preserveScroll: true,
@@ -149,7 +155,7 @@
     <template #actions>
       <CpLink
         appearance="button"
-        :href="create['/admin/settings/entry-types/new']().url"
+        :href="create['/{cpTrigger?}/settings/entry-types/new']().url"
         variant="accent"
         :inertia="false"
         icon="plus"
diff --git a/resources/js/pages/settings/Fields.vue b/resources/js/pages/settings/Fields.vue
index 7bcdf3d7127..ef517deb3d7 100644
--- a/resources/js/pages/settings/Fields.vue
+++ b/resources/js/pages/settings/Fields.vue
@@ -156,9 +156,12 @@
     initialState: props.pagination,
     onChange: ({query}) => {
       router.visit(
-        index({
-          query,
-        }),
+        index(
+          {},
+          {
+            query,
+          }
+        ),
         {
           only: ['data', 'pagination'],
           preserveScroll: true,
@@ -170,9 +173,12 @@
     initialState: props.sort,
     onChange: ({query}) => {
       router.visit(
-        index({
-          query,
-        }),
+        index(
+          {},
+          {
+            query,
+          }
+        ),
         {
           only: ['data', 'sort'],
           preserveScroll: true,
diff --git a/resources/js/pages/settings/Filesystems.vue b/resources/js/pages/settings/Filesystems.vue
index 6f37c805828..97c34b351f3 100644
--- a/resources/js/pages/settings/Filesystems.vue
+++ b/resources/js/pages/settings/Filesystems.vue
@@ -43,7 +43,7 @@
         })
       )
     ) {
-      router.delete(destroy(fs.handle));
+      router.delete(destroy({handle: fs.handle}));
     }
   }
 
@@ -61,7 +61,7 @@
     columnHelper.link('name', {
       header: t('Name'),
       props: ({row}) => ({
-        href: edit['/admin/settings/filesystems/{handle}/edit']({
+        href: edit['/{cpTrigger?}/settings/filesystems/{handle}/edit']({
           handle: row.original.handle,
         }).url,
         inertia: false,
diff --git a/resources/js/pages/settings/ImageTransforms.vue b/resources/js/pages/settings/ImageTransforms.vue
index 21af75fd536..2dfd4f21753 100644
--- a/resources/js/pages/settings/ImageTransforms.vue
+++ b/resources/js/pages/settings/ImageTransforms.vue
@@ -41,7 +41,7 @@
         })
       )
     ) {
-      router.delete(destroy(transform.id));
+      router.delete(destroy({transformId: transform.id}));
     }
   }
 
diff --git a/resources/js/pages/settings/Sections.vue b/resources/js/pages/settings/Sections.vue
index 68c31c0c154..bb4141eda14 100644
--- a/resources/js/pages/settings/Sections.vue
+++ b/resources/js/pages/settings/Sections.vue
@@ -46,8 +46,9 @@
           'a',
           {
             class: 'font-bold',
-            href: edit['/admin/settings/sections/{section}'](row.original.id)
-              .url,
+            href: edit['/{cpTrigger?}/settings/sections/{section}']({
+              section: row.original.id,
+            }).url,
           },
           getValue()
         ),
@@ -69,9 +70,12 @@
     initialState: props.pagination,
     onChange: ({query}) => {
       router.visit(
-        index({
-          query,
-        }),
+        index(
+          {},
+          {
+            query,
+          }
+        ),
         {
           only: ['data', 'pagination'],
           preserveScroll: true,
@@ -84,9 +88,12 @@
     initialState: props.sort,
     onChange: ({query}) => {
       router.visit(
-        index({
-          query,
-        }),
+        index(
+          {},
+          {
+            query,
+          }
+        ),
         {
           only: ['data', 'sort'],
           preserveScroll: true,
diff --git a/resources/js/pages/settings/Sites.vue b/resources/js/pages/settings/Sites.vue
index 50a09d51e8c..44a9a214059 100644
--- a/resources/js/pages/settings/Sites.vue
+++ b/resources/js/pages/settings/Sites.vue
@@ -105,7 +105,7 @@
         h(
           CpLink,
           {
-            href: edit.url(row.original.id),
+            href: edit.url({site: row.original.id}),
           },
           () =>
             h(
@@ -246,7 +246,7 @@
       <CpLink
         v-if="!readOnly"
         as="craft-button"
-        :href="create({query: {groupId: group?.id}}).url"
+        :href="create({}, {query: {groupId: group?.id}}).url"
         variant="accent"
         appearance="button"
       >
@@ -264,7 +264,7 @@
           as="craft-nav-item"
           v-for="g in groups"
           :key="g.id"
-          :href="index.url({query: {groupId: g.id}})"
+          :href="index.url({}, {query: {groupId: g.id}})"
           :active="group && g.id === group.id"
           block
         >
@@ -297,7 +297,7 @@
             <CpLink
               v-if="!readOnly"
               as="craft-button"
-              :href="create({query: {groupId: group?.id}}).url"
+              :href="create({}, {query: {groupId: group?.id}}).url"
               appearance="button"
             >
               <craft-icon name="plus" slot="prefix"></craft-icon>
diff --git a/resources/js/pages/settings/UserGroups.vue b/resources/js/pages/settings/UserGroups.vue
index 536aa8c4848..cd7458b6a03 100644
--- a/resources/js/pages/settings/UserGroups.vue
+++ b/resources/js/pages/settings/UserGroups.vue
@@ -29,7 +29,7 @@
         t('Are you sure you want to delete "{name}"?', {name: group.name})
       )
     ) {
-      router.delete(destroy(group.id));
+      router.delete(destroy({groupId: group.id}));
     }
   }
 
@@ -40,7 +40,7 @@
         columnHelper.link('name', {
           header: t('Name'),
           props: ({row}) => ({
-            href: edit(row.original.id).url,
+            href: edit({userGroup: row.original.id}).url,
           }),
         }),
         columnHelper.handle('handle'),
diff --git a/resources/js/pages/settings/Volumes.vue b/resources/js/pages/settings/Volumes.vue
index 349cd0e3a08..c1fb5b96673 100644
--- a/resources/js/pages/settings/Volumes.vue
+++ b/resources/js/pages/settings/Volumes.vue
@@ -58,7 +58,7 @@
         })
       )
     ) {
-      router.delete(destroy(volume.id));
+      router.delete(destroy({volumeId: volume.id}));
     }
   }
 
@@ -108,7 +108,7 @@
     columnHelper.link('name', {
       header: t('Name'),
       props: ({row}) => ({
-        href: edit(row.original.id).url,
+        href: edit({volumeId: row.original.id}).url,
         inertia: false,
       }),
     }),
diff --git a/resources/js/pages/settings/routes/Edit.vue b/resources/js/pages/settings/routes/Edit.vue
index 3cd0ff132db..b8fb30c56eb 100644
--- a/resources/js/pages/settings/routes/Edit.vue
+++ b/resources/js/pages/settings/routes/Edit.vue
@@ -38,7 +38,7 @@
   );
 
   const routeAction = () =>
-    props.route.uid ? update(props.route.uid) : store();
+    props.route.uid ? update({uid: props.route.uid}) : store();
 
   const {save: saveRoute} = useSettingsSave(form, routeAction, {
     transform: (data) => ({
diff --git a/resources/js/pages/settings/routes/Index.vue b/resources/js/pages/settings/routes/Index.vue
index 5eb048e9e3b..41d2499b9ed 100644
--- a/resources/js/pages/settings/routes/Index.vue
+++ b/resources/js/pages/settings/routes/Index.vue
@@ -74,7 +74,7 @@
       return;
     }
 
-    router.delete(destroy(route.uid));
+    router.delete(destroy({uid: route.uid}));
   }
 </script>
 
@@ -113,7 +113,7 @@
           </div>
         </div>
 
-        <Link :href="edit(route.uid)" class="route__parts">
+        <Link :href="edit({uid: route.uid})" class="route__parts">
           <div>
             <span
               v-if="route.uriDisplayHtml"
@@ -137,7 +137,7 @@
             as="craft-button"
             size="small"
             appearance="plain"
-            :href="edit(route.uid)"
+            :href="edit({uid: route.uid})"
           >
             <craft-icon name="pencil" :label="t('Edit')"></craft-icon>
           </Link>
diff --git a/resources/js/pages/updater/Index.vue b/resources/js/pages/updater/Index.vue
index dd7af27374f..340ff62fcd9 100644
--- a/resources/js/pages/updater/Index.vue
+++ b/resources/js/pages/updater/Index.vue
@@ -7,6 +7,7 @@
     type UpdaterState,
     useUpdater,
   } from '@/modules/updater/composables/useUpdater';
+  import {ConfigService} from '@craftcms/cp';
 
   const props = defineProps<{
     title: string;
@@ -41,7 +42,7 @@
   function handleFinish(): void {
     setTimeout(() => {
       window.location.href =
-        state.value.returnUrl || props.returnUrl || '/admin/dashboard';
+        state.value.returnUrl || props.returnUrl || ConfigService.getInstance().getCpUrl('dashboard');
     }, 750);
   }
 
diff --git a/routes/actions.php b/routes/actions.php
index 63ee2f2ec05..b1ce41e66e9 100644
--- a/routes/actions.php
+++ b/routes/actions.php
@@ -2,7 +2,6 @@
 
 declare(strict_types=1);
 
-use CraftCms\Cms\Cms;
 use CraftCms\Cms\Edition;
 use CraftCms\Cms\Http\Controllers\AddressesController;
 use CraftCms\Cms\Http\Controllers\AnnouncementsController;
@@ -107,21 +106,24 @@
 use CraftCms\Cms\Http\Middleware\RequireEdition;
 use CraftCms\Cms\Http\Middleware\RequireToken;
 use CraftCms\Cms\Http\Middleware\StartSessionWithoutPersistence;
+use CraftCms\Cms\Route\Routes as CraftRoutes;
 use Illuminate\Foundation\Http\Middleware\PreventRequestForgery;
 use Illuminate\Session\Middleware\StartSession;
 use Illuminate\Support\Facades\Route;
 use Illuminate\View\Middleware\ShareErrorsFromSession;
 
+$routes = app(CraftRoutes::class);
+$sharedActionRouteGroups = $routes->actionTriggerRoutePrefix() === $routes->cpActionTriggerRoutePrefix()
+    ? [[$routes->cpActionTriggerRoutePrefix(), ['craft.cp']]]
+    : [
+        [$routes->actionTriggerRoutePrefix(), ['craft.web']],
+        [$routes->cpActionTriggerRoutePrefix(), ['craft.cp']],
+    ];
+
 /**
  * Actions that are accessible both with and without CP can be registered here.
  */
-foreach ([
-    Cms::config()->actionTrigger => ['craft.web'],
-    implode('/', [
-        Cms::config()->cpTrigger,
-        Cms::config()->actionTrigger,
-    ]) => ['craft.cp'],
-] as $prefix => $middleware) {
+foreach ($sharedActionRouteGroups as [$prefix, $middleware]) {
     Route::prefix($prefix)->middleware($middleware)->group(function () use ($middleware) {
         // App
         Route::get('app/health-check', HealthCheckController::class);
@@ -158,7 +160,7 @@
 /**
  * Actions that are accessible without CP can be registered here.
  */
-Route::prefix(Cms::config()->actionTrigger)->group(function () {
+Route::prefix($routes->actionTriggerRoutePrefix())->group(function () {
     Route::post('migrate', MigrateController::class);
 
     Route::middleware(['auth'])->group(function () {
@@ -173,10 +175,7 @@
     });
 });
 
-Route::prefix(implode('/', [
-    Cms::config()->cpTrigger,
-    Cms::config()->actionTrigger,
-]))->middleware(['craft.cp'])->group(function () {
+Route::prefix($routes->cpActionTriggerRoutePrefix())->middleware(['craft.cp'])->group(function () {
     /**
      * Actions not needing auth
      */
diff --git a/routes/routes.php b/routes/routes.php
index 9d96e937e98..a95de848cf4 100644
--- a/routes/routes.php
+++ b/routes/routes.php
@@ -1,15 +1,17 @@
 <?php
 
-use CraftCms\Cms\Cms;
+use CraftCms\Cms\Route\Routes as CraftRoutes;
 use Illuminate\Support\Facades\Route;
 
+$routes = app(CraftRoutes::class);
+
 Route::middleware(['web', 'craft'])
     ->name('craft.actions.')
     ->group(__DIR__.'/actions.php');
 
 Route::middleware(['web', 'craft', 'craft.cp'])
     ->name('craft.cp.')
-    ->prefix(Cms::config()->cpTrigger)
+    ->prefix($routes->cpTriggerRoutePrefix())
     ->group(__DIR__.'/cp.php');
 
 Route::middleware(['web', 'craft', 'craft.web'])
diff --git a/routes/web.php b/routes/web.php
index b4f636a82dd..c74e83d2870 100644
--- a/routes/web.php
+++ b/routes/web.php
@@ -9,9 +9,12 @@
 use CraftCms\Cms\Http\Controllers\Auth\TwoFactorAuthenticationController;
 use CraftCms\Cms\Http\Controllers\Auth\VerifyEmailController;
 use CraftCms\Cms\Http\Middleware\RequireEdition;
+use CraftCms\Cms\Route\Routes as CraftRoutes;
 use CraftCms\Cms\Site\Sites;
 use Illuminate\Support\Facades\Route;
 
+$routes = app(CraftRoutes::class);
+
 if (Edition::get()->registersFrontendUserRoutes()) {
     if (Cms::config()->loginPath !== false) {
         Route::get(Cms::config()->loginPath, [LoginController::class, 'showLogin']);
@@ -31,11 +34,11 @@
 }
 
 if (OAuth::isAvailable()) {
-    Route::middleware([RequireEdition::class.':'.Edition::Pro->value])->group(function () {
+    Route::middleware([RequireEdition::class.':'.Edition::Pro->value])->group(function () use ($routes) {
         Route::get('oauth/{provider}/redirect', [OAuthController::class, 'redirect'])->name('oauth.redirect');
         Route::get('oauth/{provider}/callback', [OAuthController::class, 'callback'])->name('oauth.callback');
 
-        Route::prefix(Cms::config()->cpTrigger)->middleware('craft.cp')->group(function () {
+        Route::prefix($routes->cpTriggerRoutePrefix())->middleware('craft.cp')->group(function () {
             Route::get('oauth/{provider}/redirect', [OAuthController::class, 'redirect']);
         });
     });
diff --git a/src/Http/Middleware/ForgetTriggerParameters.php b/src/Http/Middleware/ForgetTriggerParameters.php
new file mode 100644
index 00000000000..f3e384efc36
--- /dev/null
+++ b/src/Http/Middleware/ForgetTriggerParameters.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace CraftCms\Cms\Http\Middleware;
+
+use Closure;
+use Illuminate\Http\Request;
+
+/**
+ * This middleware removes the cpTrigger and actionTrigger parameters
+ * from the route. Otherwise, these parameters will be added
+ * as the first parameter to every controller action.
+ */
+class ForgetTriggerParameters
+{
+    public function handle(Request $request, Closure $next): mixed
+    {
+        $request->route()?->forgetParameter('cpTrigger');
+        $request->route()?->forgetParameter('actionTrigger');
+
+        return $next($request);
+    }
+}
diff --git a/src/Http/Mixins/RequestMixin.php b/src/Http/Mixins/RequestMixin.php
index 7128201571f..d9c928e2741 100644
--- a/src/Http/Mixins/RequestMixin.php
+++ b/src/Http/Mixins/RequestMixin.php
@@ -116,10 +116,23 @@ public function isCpRequest(): Closure
              * @phpstan-ignore-next-line
              */
             $request = $this;
+            $cpTrigger = trim((string) Cms::config()->cpTrigger, '/');
+
+            if ($request->attributes->has('isCpRequest')) {
+                return (bool) $request->attributes->get('isCpRequest');
+            }
+
+            if ($request->routeIs('craft.cp.*')) {
+                return true;
+            }
+
+            if ($cpTrigger === '') {
+                return true;
+            }
 
             return $request->is(
-                Cms::config()->cpTrigger,
-                Cms::config()->cpTrigger.'/*',
+                $cpTrigger,
+                "$cpTrigger/*",
             );
         };
     }
diff --git a/src/Http/Routing/ActionRoute.php b/src/Http/Routing/ActionRoute.php
index 4c0321203ba..a188e4d8ab6 100644
--- a/src/Http/Routing/ActionRoute.php
+++ b/src/Http/Routing/ActionRoute.php
@@ -32,12 +32,11 @@ public static function fromSegments(array $segments, bool $isCp): ?self
 
     public static function uriForSegments(array $segments, bool $isCp): string
     {
-        return implode('/', array_filter([
-            '',
-            $isCp ? Cms::config()->cpTrigger : null,
-            Cms::config()->actionTrigger,
+        return '/'.implode('/', array_filter([
+            $isCp ? trim((string) Cms::config()->cpTrigger, '/') : null,
+            trim(Cms::config()->actionTrigger, '/'),
             ...$segments,
-        ], fn ($value) => $value !== null));
+        ], fn (?string $value) => $value !== null && $value !== ''));
     }
 
     public function matches(Request $request): bool
diff --git a/src/Http/Routing/ActionRouteResolver.php b/src/Http/Routing/ActionRouteResolver.php
index 0600cc92f4b..585d135ff7b 100644
--- a/src/Http/Routing/ActionRouteResolver.php
+++ b/src/Http/Routing/ActionRouteResolver.php
@@ -34,8 +34,8 @@ public function resolve(Request $request): ?ActionRoute
 
     private function segmentsFromPath(Request $request): ?array
     {
-        $actionTrigger = Cms::config()->actionTrigger;
-        $segmentIndex = $request->isCpRequest() ? 2 : 1;
+        $actionTrigger = trim(Cms::config()->actionTrigger, '/');
+        $segmentIndex = $this->actionTriggerSegmentIndex($request);
 
         if ($request->segment($segmentIndex) === $actionTrigger && count($request->segments()) > $segmentIndex) {
             return array_slice($request->segments(), $segmentIndex);
@@ -60,4 +60,13 @@ private function segmentsFromActionParam(Request $request): ?array
 
         return $segments === [] ? null : $segments;
     }
+
+    private function actionTriggerSegmentIndex(Request $request): int
+    {
+        if (! $request->isCpRequest()) {
+            return 1;
+        }
+
+        return trim((string) Cms::config()->cpTrigger, '/') === '' ? 1 : 2;
+    }
 }
diff --git a/src/Plugin/Concerns/HasRoutes.php b/src/Plugin/Concerns/HasRoutes.php
index 2a0452bcc04..55fd14b2203 100644
--- a/src/Plugin/Concerns/HasRoutes.php
+++ b/src/Plugin/Concerns/HasRoutes.php
@@ -5,8 +5,8 @@
 namespace CraftCms\Cms\Plugin\Concerns;
 
 use Closure;
-use CraftCms\Cms\Cms;
 use CraftCms\Cms\Plugin\Plugin;
+use CraftCms\Cms\Route\Routes;
 
 /**
  * @mixin Plugin
@@ -41,31 +41,39 @@ protected function registerWebRoutes(string|Closure $routes): void
 
     protected function registerCpRoutes(string|Closure $routes): void
     {
+        $craftRoutes = $this->app->get(Routes::class);
+
         $this->app['router']
             ->middleware(['web', 'craft', 'craft.cp'])
-            ->prefix(Cms::config()->cpTrigger)
+            ->prefix($craftRoutes->cpTriggerRoutePrefix())
             ->group($routes);
     }
 
     protected function registerActionRoutes(string|Closure $routes): void
     {
         $handle = self::getInstance()->handle;
+        $craftRoutes = $this->app->get(Routes::class);
+        $cpActionPrefix = $craftRoutes->joinRoutePrefix([
+            $craftRoutes->cpActionTriggerRoutePrefix(),
+            $handle,
+        ]);
+        $siteActionPrefix = $craftRoutes->joinRoutePrefix([
+            $craftRoutes->actionTriggerRoutePrefix(),
+            $handle,
+        ]);
 
         $this->app['router']
             ->middleware(['web', 'craft', 'craft.cp'])
-            ->prefix(implode('/', [
-                Cms::config()->cpTrigger,
-                Cms::config()->actionTrigger,
-                $handle,
-            ]))
+            ->prefix($cpActionPrefix)
             ->group($routes);
 
+        if ($siteActionPrefix === $cpActionPrefix) {
+            return;
+        }
+
         $this->app['router']
             ->middleware(['craft', 'craft.web'])
-            ->prefix(implode('/', [
-                Cms::config()->actionTrigger,
-                $handle,
-            ]))
+            ->prefix($siteActionPrefix)
             ->group($routes);
     }
 }
diff --git a/src/Route/RouteServiceProvider.php b/src/Route/RouteServiceProvider.php
index 3d91eb34af8..5b15e9d618f 100644
--- a/src/Route/RouteServiceProvider.php
+++ b/src/Route/RouteServiceProvider.php
@@ -18,6 +18,7 @@
 use CraftCms\Cms\Http\Middleware\EnforceLicenses;
 use CraftCms\Cms\Http\Middleware\EnsureInstalled;
 use CraftCms\Cms\Http\Middleware\ExtractNamespace;
+use CraftCms\Cms\Http\Middleware\ForgetTriggerParameters;
 use CraftCms\Cms\Http\Middleware\HandleActionRequest;
 use CraftCms\Cms\Http\Middleware\HandleInertiaRequests;
 use CraftCms\Cms\Http\Middleware\HandleMatchedElementRoute;
@@ -43,6 +44,7 @@
 use Illuminate\Session\Middleware\AuthenticateSession;
 use Illuminate\Support\Facades\Event;
 use Illuminate\Support\Facades\RateLimiter;
+use Illuminate\Support\Facades\URL;
 use Illuminate\Support\ServiceProvider;
 use Override;
 
@@ -72,6 +74,11 @@ public function register(): void
 
     public function boot(Router $router, Routes $routes): void
     {
+        URL::defaults([
+            'cpTrigger' => trim((string) Cms::config()->cpTrigger, '/') ?: null,
+            'actionTrigger' => trim(Cms::config()->actionTrigger, '/'),
+        ]);
+
         $router->patterns($routes->tokens);
 
         $this->bootMiddleware($router);
@@ -124,8 +131,8 @@ private function bootRequestForgeryExceptions(): void
             'preview/preview',
         ])->flatMap(fn (string $route) => [
             $route,
-            Cms::config()->actionTrigger.Str::start($route, '/'),
-            Cms::config()->cpTrigger.'/'.Cms::config()->actionTrigger.Str::start($route, '/'),
+            app(Routes::class)->actionTriggerUriPrefix().Str::start($route, '/'),
+            app(Routes::class)->cpActionTriggerUriPrefix().Str::start($route, '/'),
         ])->all());
     }
 
@@ -151,6 +158,7 @@ private function bootMaintenanceModeExceptions(): void
     private function bootMiddleware(Router $router): void
     {
         collect([
+            ForgetTriggerParameters::class,
             EnsureInstalled::class,
             AddLogContext::class,
             ResolveSite::class,
diff --git a/src/Route/Routes.php b/src/Route/Routes.php
index 7b80d7cc831..c5d7c75332e 100644
--- a/src/Route/Routes.php
+++ b/src/Route/Routes.php
@@ -32,10 +32,51 @@ class Routes
             'handle' => '[^\/]+',
             'slug' => '[^\/]+',
             'tag' => '[^\/]+',
+            'cpTrigger' => preg_quote(trim((string) Cms::config()->cpTrigger, '/'), '#') ?: '(?!)',
+            'actionTrigger' => preg_quote(trim(Cms::config()->actionTrigger, '/'), '#') ?: '(?!)',
             '*' => '[^\/]+',
         ];
     }
 
+    public function cpTriggerRoutePrefix(): string
+    {
+        return trim((string) Cms::config()->cpTrigger, '/') === '' ? '' : '{cpTrigger}';
+    }
+
+    public function actionTriggerRoutePrefix(): string
+    {
+        return trim(Cms::config()->actionTrigger, '/') === '' ? '' : '{actionTrigger}';
+    }
+
+    public function cpActionTriggerRoutePrefix(): string
+    {
+        return $this->joinRoutePrefix([
+            $this->cpTriggerRoutePrefix(),
+            $this->actionTriggerRoutePrefix(),
+        ]);
+    }
+
+    public function actionTriggerUriPrefix(): string
+    {
+        return trim(Cms::config()->actionTrigger, '/');
+    }
+
+    public function cpActionTriggerUriPrefix(): string
+    {
+        return $this->joinRoutePrefix([
+            trim((string) Cms::config()->cpTrigger, '/'),
+            $this->actionTriggerUriPrefix(),
+        ]);
+    }
+
+    public function joinRoutePrefix(array $segments): string
+    {
+        return implode('/', array_filter(
+            $segments,
+            fn (?string $segment) => $segment !== null && $segment !== '',
+        ));
+    }
+
     /**
      * @var array|null all the routes in project config for current site
      */
diff --git a/tests/Feature/Http/Controllers/Settings/FilesystemsControllerTest.php b/tests/Feature/Http/Controllers/Settings/FilesystemsControllerTest.php
index 2c6ed15fca2..68f77b4bdb2 100644
--- a/tests/Feature/Http/Controllers/Settings/FilesystemsControllerTest.php
+++ b/tests/Feature/Http/Controllers/Settings/FilesystemsControllerTest.php
@@ -86,7 +86,7 @@
 
 test('edit returns 200 for non-existent filesystem handle and shows create form', function () {
     // Non-existent handles are treated as new filesystem creation
-    $response = get(action([FilesystemsController::class, 'edit'], ['non-existent-handle']));
+    $response = get(action([FilesystemsController::class, 'edit'], ['handle' => 'non-existent-handle']));
 
     $response
         ->assertOk()
@@ -106,7 +106,7 @@
 
     Filesystems::saveFilesystem($fs);
 
-    $response = get(action([FilesystemsController::class, 'edit'], ['testFilesystem']));
+    $response = get(action([FilesystemsController::class, 'edit'], ['handle' => 'testFilesystem']));
 
     $response->assertOk();
 
@@ -129,7 +129,7 @@
 
     Filesystems::saveFilesystem($fs);
 
-    $response = get(action([FilesystemsController::class, 'edit'], ['testFilesystemActions']));
+    $response = get(action([FilesystemsController::class, 'edit'], ['handle' => 'testFilesystemActions']));
 
     $response->assertOk();
 });
diff --git a/tests/Unit/Http/Middleware/HandleActionRequestTest.php b/tests/Unit/Http/Middleware/HandleActionRequestTest.php
index 00b7a0c617b..9b7104205e2 100644
--- a/tests/Unit/Http/Middleware/HandleActionRequestTest.php
+++ b/tests/Unit/Http/Middleware/HandleActionRequestTest.php
@@ -28,6 +28,26 @@
         ->and($handledRequest->attributes->get(ActionRoute::class))->toBeInstanceOf(ActionRoute::class);
 });
 
+it('rebinds rewritten root control panel action requests as the current request', function (?string $cpTrigger) {
+    Cms::config()->cpTrigger = $cpTrigger;
+    $request = Request::create('/utilities/query', 'POST', [
+        'action' => 'query/execute',
+    ]);
+    app()->instance('request', $request);
+
+    $handledRequest = app(HandleActionRequest::class)->handle(
+        $request,
+        fn (Request $request) => $request,
+    );
+
+    expect($handledRequest->path())->toBe('actions/query/execute')
+        ->and(request())->toBe($handledRequest)
+        ->and($handledRequest->attributes->get(ActionRoute::class))->toBeInstanceOf(ActionRoute::class);
+})->with([
+    'null' => [null],
+    'slash' => ['/'],
+]);
+
 it('does not rebind action requests that already use the normalized action uri', function () {
     $request = Request::create('/admin/actions/query/execute', 'POST');
     app()->instance('request', $request);
diff --git a/tests/Unit/Http/RequestMixinTest.php b/tests/Unit/Http/RequestMixinTest.php
index fb59e64df08..891dbab0b84 100644
--- a/tests/Unit/Http/RequestMixinTest.php
+++ b/tests/Unit/Http/RequestMixinTest.php
@@ -90,6 +90,15 @@ public function getRememberTokenName()
     it('returns false for site requests', function () {
         expect(Request::create('/news')->isCpRequest())->toBeFalse();
     });
+
+    it('returns true for root control panel requests', function (?string $cpTrigger) {
+        Cms::config()->cpTrigger = $cpTrigger;
+
+        expect(Request::create('/dashboard')->isCpRequest())->toBeTrue();
+    })->with([
+        'null' => [null],
+        'slash' => ['/'],
+    ]);
 });
 
 describe('getToken', function () {
diff --git a/tests/Unit/Http/Routing/ActionRouteResolverTest.php b/tests/Unit/Http/Routing/ActionRouteResolverTest.php
index 82dfc7d7cad..fcfcb76f7b1 100644
--- a/tests/Unit/Http/Routing/ActionRouteResolverTest.php
+++ b/tests/Unit/Http/Routing/ActionRouteResolverTest.php
@@ -36,6 +36,18 @@
         ->and($actionRoute->isCp)->toBeTrue();
 });
 
+it('resolves root control panel action routes from the request path', function () {
+    Cms::config()->cpTrigger = null;
+    $request = Request::create('/actions/users/login');
+
+    $actionRoute = app(ActionRouteResolver::class)->resolve($request);
+
+    expect($actionRoute)->toBeInstanceOf(ActionRoute::class)
+        ->and($actionRoute->segments)->toBe(['users', 'login'])
+        ->and($actionRoute->uri)->toBe('/actions/users/login')
+        ->and($actionRoute->isCp)->toBeTrue();
+});
+
 it('resolves action routes from the action param', function () {
     $request = Request::create('/admin/utilities/query', 'POST', [
         'action' => 'query/execute',
@@ -70,3 +82,12 @@
     expect(ActionRoute::uriForSegments(['users', 'login'], false))->toBe('/actions/users/login')
         ->and(ActionRoute::uriForSegments(['users', 'login'], true))->toBe('/admin/actions/users/login');
 });
+
+it('builds root control panel action uris from explicit segments', function (?string $cpTrigger) {
+    Cms::config()->cpTrigger = $cpTrigger;
+
+    expect(ActionRoute::uriForSegments(['users', 'login'], true))->toBe('/actions/users/login');
+})->with([
+    'null' => [null],
+    'slash' => ['/'],
+]);
diff --git a/tests/Unit/Plugin/Concerns/HasRoutesTest.php b/tests/Unit/Plugin/Concerns/HasRoutesTest.php
index 3c8a9784c09..232b2da4f84 100644
--- a/tests/Unit/Plugin/Concerns/HasRoutesTest.php
+++ b/tests/Unit/Plugin/Concerns/HasRoutesTest.php
@@ -36,15 +36,47 @@
         ->all();
 
     expect($uris)->toContain('plugin-web')
-        ->and($uris)->toContain('admin/plugin-cp')
-        ->and($uris)->toContain('admin/actions/test-plugin/plugin-action')
-        ->and($uris)->toContain('actions/test-plugin/plugin-action')
-        ->and($uris)->not()->toContain('admin/actions/plugin-action')
-        ->and($uris)->not()->toContain('actions/plugin-action');
+        ->and($uris)->toContain('{cpTrigger}/plugin-cp')
+        ->and($uris)->toContain('{cpTrigger}/{actionTrigger}/test-plugin/plugin-action')
+        ->and($uris)->toContain('{actionTrigger}/test-plugin/plugin-action')
+        ->and($uris)->not()->toContain('{cpTrigger}/{actionTrigger}/plugin-action')
+        ->and($uris)->not()->toContain('{actionTrigger}/plugin-action');
 
     $routesByUri = collect(Route::getRoutes()->getRoutes())
         ->keyBy(fn ($route) => $route->uri());
 
-    expect($routesByUri->get('admin/plugin-cp')->middleware())->toContain('web', 'craft', 'craft.cp')
-        ->and($routesByUri->get('admin/actions/test-plugin/plugin-action')->middleware())->toContain('web', 'craft', 'craft.cp');
+    expect($routesByUri->get('{cpTrigger}/plugin-cp')->middleware())->toContain('web', 'craft', 'craft.cp')
+        ->and($routesByUri->get('{cpTrigger}/{actionTrigger}/test-plugin/plugin-action')->middleware())->toContain('web', 'craft', 'craft.cp');
+});
+
+it('registers root control panel routes when the cp trigger is null', function () {
+    /** @var GeneralConfig $config */
+    $config = app(GeneralConfig::class);
+    $config->cpTrigger = null;
+    $config->actionTrigger = 'actions';
+
+    $plugin = TestPlugin::create([
+        'handle' => 'test-plugin',
+        'name' => 'Test Plugin',
+    ]);
+
+    $plugin->useBasePath($this->basePath);
+    $plugin->bootHasRoutes();
+
+    $routes = collect(Route::getRoutes()->getRoutes());
+    $uris = $routes
+        ->map(fn ($route) => $route->uri())
+        ->all();
+
+    expect($uris)->toContain('plugin-web')
+        ->and($uris)->toContain('plugin-cp')
+        ->and($uris)->toContain('{actionTrigger}/test-plugin/plugin-action')
+        ->and($uris)->not()->toContain('{cpTrigger}/plugin-cp')
+        ->and($uris)->not()->toContain('{cpTrigger}/{actionTrigger}/test-plugin/plugin-action');
+
+    $pluginActionRoutes = $routes->filter(fn ($route) => $route->uri() === '{actionTrigger}/test-plugin/plugin-action');
+
+    expect($routes->first(fn ($route) => $route->uri() === 'plugin-cp')->middleware())->toContain('web', 'craft', 'craft.cp');
+    expect($pluginActionRoutes)->toHaveCount(1)
+        ->and($pluginActionRoutes->first()->middleware())->toContain('web', 'craft', 'craft.cp');
 });