diff --git a/frontend-next-migration/src/app/[lng]/(helper)/admin/_components/AuthRefreshTest.tsx b/frontend-next-migration/src/app/[lng]/(helper)/admin/_components/AuthRefreshTest.tsx
new file mode 100644
index 000000000..fc8cc5b3b
--- /dev/null
+++ b/frontend-next-migration/src/app/[lng]/(helper)/admin/_components/AuthRefreshTest.tsx
@@ -0,0 +1,64 @@
+'use client';
+import { useState } from 'react';
+import { useSelector } from 'react-redux';
+import {
+    selectAuthUserState,
+    useRefreshAuthMutation,
+    AccessTokenInfoResponse,
+    AuthUserSchema,
+} from '@/entities/Auth';
+import { LS_KEYS } from '@/shared/const/LS_KEYS';
+
+const AuthRefreshTest = () => {
+    const [refreshAuth, { isLoading, error }] = useRefreshAuthMutation();
+    const authUser = useSelector((state: { authUser: AuthUserSchema }) =>
+        selectAuthUserState(state),
+    );
+    const [response, setResponse] = useState<AccessTokenInfoResponse | null>(null);
+    const [refreshToken, setRefreshToken] = useState('');
+    const [storedAuthUser, setStoredAuthUser] = useState<string | null>(null);
+
+    const handleRefresh = async () => {
+        try {
+            const refreshResponse = await refreshAuth({ refreshToken }).unwrap();
+            setResponse(refreshResponse);
+            setStoredAuthUser(localStorage.getItem(LS_KEYS.AUTH_USER));
+        } catch {
+            setResponse(null);
+            setStoredAuthUser(localStorage.getItem(LS_KEYS.AUTH_USER));
+        }
+    };
+
+    return (
+        <section>
+            <h2>Auth refresh test</h2>
+            <label htmlFor="refresh-token">Refresh token</label>
+            <input
+                id="refresh-token"
+                type="text"
+                required
+                value={refreshToken}
+                onChange={(event) => setRefreshToken(event.target.value)}
+            />
+            <br />
+            <button
+                type="button"
+                onClick={handleRefresh}
+                disabled={isLoading || !refreshToken}
+            >
+                {isLoading ? 'Refreshing...' : 'Refresh auth'}
+            </button>
+            {error && <pre>{JSON.stringify(error, null, 2)}</pre>}
+            {response && <pre>{JSON.stringify(response, null, 2)}</pre>}
+            <br />
+            <h3>Redux auth state</h3>
+            <pre>{JSON.stringify(authUser, null, 2)}</pre>
+            <br />
+            <h3>localStorage AuthUser after request</h3>
+            <pre>{storedAuthUser ?? 'No localStorage snapshot yet'}</pre>
+            <br />
+        </section>
+    );
+};
+
+export default AuthRefreshTest;
diff --git a/frontend-next-migration/src/app/[lng]/(helper)/admin/page.tsx b/frontend-next-migration/src/app/[lng]/(helper)/admin/page.tsx
index a11f237b2..97c107cc6 100644
--- a/frontend-next-migration/src/app/[lng]/(helper)/admin/page.tsx
+++ b/frontend-next-migration/src/app/[lng]/(helper)/admin/page.tsx
@@ -10,6 +10,7 @@ import NewsCardsGrid from './_components/NewsCardsGrid';
 import DescriptionCardsSection from './_components/DescriptionCardsSection';
 import MobileCardsGrid from './_components/MobileCardsGrid';
 import BarIndicatorBlock from '@/app/[lng]/(helper)/admin/_components/BarIndicatorBlock';
+import AuthRefreshTest from './_components/AuthRefreshTest';
 import useSizes from '@/shared/lib/hooks/useSizes';
 import hannu from '@/shared/assets/images/heros/hannu-hodari/hannu-hodari.png';
 import vihapuhe from '@/shared/assets/images/heros/hate-speech/Vihapuhe.png';
@@ -48,6 +49,8 @@ const Page = () => {
                 component: <NavMenusBlock variant="forum" />,
             }}
         >
+            <AuthRefreshTest />
+
             <button
                 style={{
                     paddingLeft: '1em',
diff --git a/frontend-next-migration/src/entities/Auth/index.ts b/frontend-next-migration/src/entities/Auth/index.ts
index e4937c820..0cbd1f73a 100644
--- a/frontend-next-migration/src/entities/Auth/index.ts
+++ b/frontend-next-migration/src/entities/Auth/index.ts
@@ -1,6 +1,7 @@
 export type {
     IUserRegisterDto,
     IUserLoginDto,
+    IRefreshAuthDto,
     IPlayerRegisterPartDto,
     AuthUserSchema,
     ILoginResponse,
@@ -11,6 +12,7 @@ export {
     useLoginMutation,
     useRegisterMutation,
     useLogoutMutation,
+    useRefreshAuthMutation,
     authEndpoints,
 } from './model/authApi';
 
diff --git a/frontend-next-migration/src/entities/Auth/middlewares/README.md b/frontend-next-migration/src/entities/Auth/middlewares/README.md
new file mode 100644
index 000000000..56905b635
--- /dev/null
+++ b/frontend-next-migration/src/entities/Auth/middlewares/README.md
@@ -0,0 +1,15 @@
+# Authentication refresh investigation
+
+## Current implementation
+
+`authApi.ts` exposes `refreshAuth` as a `POST /auth/refresh` mutation with the required `{ refreshToken }` JSON body. It returns `AccessTokenInfoResponse`, containing the new access and refresh tokens. The mutation is intentionally not called by production authentication code yet.
+
+The admin page contains a manual probe at `/{lng}/admin`. It displays the refresh response, the current Redux auth state, and an `AuthUser` localStorage snapshot after the request. This makes it possible to verify the backend contract without changing the normal login flow.
+
+## Middleware findings
+
+The existing middleware can observe a successful RTK Query mutation with `authEndpoints.refreshAuth.matchFulfilled(action)`. A future integration could then dispatch `authUserActions.setAccessTokenInfo` with the refreshed token and its calculated expiry. The existing `setAccessTokenInfo` branch would persist that state to localStorage.
+
+The middleware should not start the refresh request itself on every action. It is synchronous, and a request started from the middleware would need a separate expiry trigger, concurrency guard, and failure path. A `baseQuery` wrapper that retries an expired request once after dispatching `refreshAuth` is a better fit for automatic refresh. It must also prevent refresh loops and coordinate concurrent requests.
+
+Before wiring this into production, verify the endpoint response and refresh-cookie behavior with the admin probe. If the response expiry field is not `accessTokenExpiresInSecIn`, update `AccessTokenInfoResponse` and the expiry mapping together.
diff --git a/frontend-next-migration/src/entities/Auth/model/authApi.test.ts b/frontend-next-migration/src/entities/Auth/model/authApi.test.ts
new file mode 100644
index 000000000..b0e77cedb
--- /dev/null
+++ b/frontend-next-migration/src/entities/Auth/model/authApi.test.ts
@@ -0,0 +1,13 @@
+import { authEndpoints, useRefreshAuthMutation } from './authApi';
+
+describe('authApi refresh endpoint', () => {
+    it('exposes the refreshAuth mutation and React hook', () => {
+        expect(authEndpoints.refreshAuth).toEqual(
+            expect.objectContaining({
+                initiate: expect.any(Function),
+                matchFulfilled: expect.any(Function),
+            }),
+        );
+        expect(useRefreshAuthMutation).toEqual(expect.any(Function));
+    });
+});
diff --git a/frontend-next-migration/src/entities/Auth/model/authApi.ts b/frontend-next-migration/src/entities/Auth/model/authApi.ts
index f75b4b6df..e57f60a1f 100644
--- a/frontend-next-migration/src/entities/Auth/model/authApi.ts
+++ b/frontend-next-migration/src/entities/Auth/model/authApi.ts
@@ -1,5 +1,11 @@
 import { gameApi } from '@/shared/api';
-import { IUserRegisterDto, IUserLoginDto, ILoginResponse } from '../types/authUser';
+import {
+    IUserRegisterDto,
+    IUserLoginDto,
+    IRefreshAuthDto,
+    ILoginResponse,
+    AccessTokenInfoResponse,
+} from '../types/authUser';
 
 const authApi = gameApi.injectEndpoints({
     endpoints: (builder) => ({
@@ -23,6 +29,13 @@ const authApi = gameApi.injectEndpoints({
                 method: 'POST',
             }),
         }),
+        refreshAuth: builder.mutation<AccessTokenInfoResponse, IRefreshAuthDto>({
+            query: (refreshAuthDto) => ({
+                url: '/auth/refresh',
+                method: 'POST',
+                body: refreshAuthDto,
+            }),
+        }),
     }),
     overrideExisting: false,
 });
@@ -31,5 +44,6 @@ export const {
     useLoginMutation,
     useRegisterMutation,
     useLogoutMutation,
+    useRefreshAuthMutation,
     endpoints: authEndpoints,
 } = authApi;
diff --git a/frontend-next-migration/src/entities/Auth/types/authUser.d.ts b/frontend-next-migration/src/entities/Auth/types/authUser.d.ts
index 2c8b5f67b..12a5b56f9 100644
--- a/frontend-next-migration/src/entities/Auth/types/authUser.d.ts
+++ b/frontend-next-migration/src/entities/Auth/types/authUser.d.ts
@@ -14,12 +14,17 @@ export type IUserRegisterDto = Pick<IProfile<IPlayer>, 'username'> & {
 
 export type IUserLoginDto = Pick<IProfile<IPlayer>, 'username'> & { password: string };
 
+export type IRefreshAuthDto = {
+    refreshToken: string;
+};
+
 export type ILoginResponse = IProfile<IPlayer> & {
     accessToken: string;
 };
 
 export type AccessTokenInfoResponse = {
     accessToken: string;
+    refreshToken: string;
     accessTokenExpiresInSecIn: number;
 };