diff --git a/extensions/general/cloud-backup/lib/google-oauth.ts b/extensions/general/cloud-backup/lib/google-oauth.ts
index 9eeefd85..004c137c 100644
--- a/extensions/general/cloud-backup/lib/google-oauth.ts
+++ b/extensions/general/cloud-backup/lib/google-oauth.ts
@@ -7,6 +7,12 @@
  *   re-issued even if the user has previously authorised the app.
  */
 
+import {
+  fetchWithTimeout,
+  OAUTH_TIMEOUT_MS,
+  OAUTH_REVOKE_TIMEOUT_MS,
+} from '@/lib/http/fetch-with-timeout'
+
 const DRIVE_SCOPE = 'https://www.googleapis.com/auth/drive.file'
 const AUTH_ENDPOINT = 'https://accounts.google.com/o/oauth2/v2/auth'
 const TOKEN_ENDPOINT = 'https://oauth2.googleapis.com/token'
@@ -65,11 +71,15 @@ export async function exchangeCodeForTokens(
     redirect_uri: env.redirectUri,
     grant_type: 'authorization_code',
   })
-  const res = await fetch(TOKEN_ENDPOINT, {
-    method: 'POST',
-    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
-    body: body.toString(),
-  })
+  const res = await fetchWithTimeout(
+    TOKEN_ENDPOINT,
+    {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+      body: body.toString(),
+    },
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Google token exchange' },
+  )
   if (!res.ok) {
     const errText = await res.text()
     throw new Error(`Google token exchange failed: ${res.status} ${errText}`)
@@ -99,11 +109,15 @@ export async function refreshAccessToken(
     refresh_token: refreshToken,
     grant_type: 'refresh_token',
   })
-  const res = await fetch(TOKEN_ENDPOINT, {
-    method: 'POST',
-    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
-    body: body.toString(),
-  })
+  const res = await fetchWithTimeout(
+    TOKEN_ENDPOINT,
+    {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+      body: body.toString(),
+    },
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Google token refresh' },
+  )
   if (!res.ok) {
     const errText = await res.text()
     throw new Error(`Google token refresh failed: ${res.status} ${errText}`)
@@ -112,16 +126,28 @@ export async function refreshAccessToken(
 }
 
 export async function revokeToken(token: string): Promise<void> {
-  await fetch(`https://oauth2.googleapis.com/revoke?token=${encodeURIComponent(token)}`, {
-    method: 'POST',
-    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
-  })
+  try {
+    await fetchWithTimeout(
+      `https://oauth2.googleapis.com/revoke?token=${encodeURIComponent(token)}`,
+      {
+        method: 'POST',
+        headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+      },
+      { timeoutMs: OAUTH_REVOKE_TIMEOUT_MS, description: 'Google token revoke' },
+    )
+  } catch {
+    // Best-effort revoke: swallow timeouts and network errors so disconnect flows still complete locally.
+  }
 }
 
 export async function fetchUserEmail(accessToken: string): Promise<string> {
-  const res = await fetch(USERINFO_ENDPOINT, {
-    headers: { Authorization: `Bearer ${accessToken}` },
-  })
+  const res = await fetchWithTimeout(
+    USERINFO_ENDPOINT,
+    {
+      headers: { Authorization: `Bearer ${accessToken}` },
+    },
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Google userinfo fetch' },
+  )
   if (!res.ok) {
     throw new Error(`Failed to fetch Google user info: ${res.status}`)
   }
diff --git a/extensions/general/skatteverket/index.ts b/extensions/general/skatteverket/index.ts
index d43e3049..51da6311 100644
--- a/extensions/general/skatteverket/index.ts
+++ b/extensions/general/skatteverket/index.ts
@@ -1,6 +1,7 @@
 import crypto from 'crypto'
 import type { Extension, ExtensionContext } from '@/lib/extensions/types'
 import { NextResponse } from 'next/server'
+import { TimeoutError } from '@/lib/http/fetch-with-timeout'
 import { buildAuthorizeUrl, exchangeCodeForTokens } from './lib/oauth'
 import { storeTokens, getTokens, deleteTokens } from './lib/token-store'
 import { skvRequest, SkatteverketAuthError } from './lib/api-client'
@@ -162,10 +163,15 @@ export const skatteverketExtension: Extension = {
           )
         } catch (err) {
           console.error('[skatteverket] Token exchange failed:', err)
+          // BankID auth codes expire after 5 minutes. Surface timeouts distinctly
+          // so the user retries quickly instead of exhausting the code window.
+          const message = err instanceof TimeoutError
+            ? 'Tidsgränsen mot Skatteverket överskreds — försök igen med BankID'
+            : err instanceof Error
+              ? err.message
+              : 'Token exchange misslyckades'
           return NextResponse.redirect(
-            `${appUrl}/reports?tab=vat-declaration&skv_error=${encodeURIComponent(
-              err instanceof Error ? err.message : 'Token exchange misslyckades'
-            )}`
+            `${appUrl}/reports?tab=vat-declaration&skv_error=${encodeURIComponent(message)}`
           )
         }
       },
diff --git a/extensions/general/skatteverket/lib/oauth.ts b/extensions/general/skatteverket/lib/oauth.ts
index 1ed0b838..6b3fa394 100644
--- a/extensions/general/skatteverket/lib/oauth.ts
+++ b/extensions/general/skatteverket/lib/oauth.ts
@@ -1,4 +1,9 @@
 import type { SkatteverketTokens } from '../types'
+import {
+  fetchWithTimeout,
+  OAUTH_TIMEOUT_MS,
+  SKATTEVERKET_EXCHANGE_TIMEOUT_MS,
+} from '@/lib/http/fetch-with-timeout'
 
 /**
  * Skatteverket OAuth2 helpers for the `per` (BankID) flow.
@@ -68,11 +73,18 @@ export async function exchangeCodeForTokens(
     code,
   })
 
-  const response = await fetch(`${base}/token`, {
-    method: 'POST',
-    headers: { 'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8' },
-    body: body.toString(),
-  })
+  const response = await fetchWithTimeout(
+    `${base}/token`,
+    {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8' },
+      body: body.toString(),
+    },
+    {
+      timeoutMs: SKATTEVERKET_EXCHANGE_TIMEOUT_MS,
+      description: 'Skatteverket token exchange',
+    },
+  )
 
   if (!response.ok) {
     const text = await response.text()
@@ -110,11 +122,18 @@ export async function refreshAccessToken(
     refresh_token: refreshToken,
   })
 
-  const response = await fetch(`${base}/token`, {
-    method: 'POST',
-    headers: { 'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8' },
-    body: body.toString(),
-  })
+  const response = await fetchWithTimeout(
+    `${base}/token`,
+    {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8' },
+      body: body.toString(),
+    },
+    {
+      timeoutMs: OAUTH_TIMEOUT_MS,
+      description: 'Skatteverket token refresh',
+    },
+  )
 
   if (!response.ok) {
     const text = await response.text()
diff --git a/lib/errors/get-error-message.ts b/lib/errors/get-error-message.ts
index 81d4948f..3d335160 100644
--- a/lib/errors/get-error-message.ts
+++ b/lib/errors/get-error-message.ts
@@ -86,6 +86,10 @@ const ERROR_PATTERN_MAP: [RegExp, string | null][] = [
     /Entry date .+ is outside fiscal period/i,
     'Datumet ligger utanför det valda räkenskapsåret.',
   ],
+  [
+    /timed out after \d+m?s/i,
+    'Anslutningen mot tjänsten tog för lång tid. Försök igen.',
+  ],
 ]
 
 /**
diff --git a/lib/http/__tests__/fetch-with-timeout.test.ts b/lib/http/__tests__/fetch-with-timeout.test.ts
new file mode 100644
index 00000000..971197b1
--- /dev/null
+++ b/lib/http/__tests__/fetch-with-timeout.test.ts
@@ -0,0 +1,124 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest'
+import { fetchWithTimeout, TimeoutError } from '../fetch-with-timeout'
+
+describe('fetchWithTimeout', () => {
+  const originalFetch = globalThis.fetch
+
+  beforeEach(() => {
+    vi.resetAllMocks()
+  })
+
+  afterEach(() => {
+    globalThis.fetch = originalFetch
+  })
+
+  it('returns the response when fetch resolves before the deadline', async () => {
+    const mockResponse = new Response('ok', { status: 200 })
+    globalThis.fetch = vi.fn().mockResolvedValue(mockResponse)
+
+    const result = await fetchWithTimeout(
+      'https://example.test/',
+      { method: 'POST' },
+      { timeoutMs: 1000, description: 'test fetch' },
+    )
+
+    expect(result).toBe(mockResponse)
+    expect(globalThis.fetch).toHaveBeenCalledOnce()
+  })
+
+  it('throws TimeoutError when fetch hangs past the timeout', async () => {
+    globalThis.fetch = vi.fn().mockImplementation((_url, init?: RequestInit) => {
+      return new Promise((_resolve, reject) => {
+        const signal = init?.signal
+        if (!signal) return
+        signal.addEventListener('abort', () => {
+          const reason = (signal as AbortSignal & { reason?: unknown }).reason
+          const err = new Error('aborted')
+          err.name =
+            reason instanceof DOMException ? reason.name : 'AbortError'
+          reject(err)
+        })
+      })
+    })
+
+    const start = Date.now()
+    await expect(
+      fetchWithTimeout(
+        'https://example.test/',
+        { method: 'POST' },
+        { timeoutMs: 50, description: 'slow fetch' },
+      ),
+    ).rejects.toBeInstanceOf(TimeoutError)
+    const elapsed = Date.now() - start
+    expect(elapsed).toBeGreaterThanOrEqual(40)
+    expect(elapsed).toBeLessThan(1000)
+  })
+
+  it('includes the description and timeout ms in the error message', async () => {
+    globalThis.fetch = vi.fn().mockImplementation((_url, init?: RequestInit) => {
+      return new Promise((_resolve, reject) => {
+        const signal = init?.signal
+        signal?.addEventListener('abort', () => {
+          const err = new Error('aborted')
+          err.name = 'TimeoutError'
+          reject(err)
+        })
+      })
+    })
+
+    try {
+      await fetchWithTimeout(
+        'https://example.test/',
+        { method: 'POST' },
+        { timeoutMs: 50, description: 'Fortnox token exchange' },
+      )
+      expect.fail('expected TimeoutError to be thrown')
+    } catch (err) {
+      expect(err).toBeInstanceOf(TimeoutError)
+      expect((err as Error).name).toBe('TimeoutError')
+      expect((err as Error).message).toContain('Fortnox token exchange')
+      expect((err as Error).message).toContain('50')
+    }
+  })
+
+  it('propagates non-timeout errors unchanged', async () => {
+    const networkError = new TypeError('fetch failed')
+    globalThis.fetch = vi.fn().mockRejectedValue(networkError)
+
+    await expect(
+      fetchWithTimeout(
+        'https://example.test/',
+        { method: 'POST' },
+        { timeoutMs: 1000, description: 'test fetch' },
+      ),
+    ).rejects.toBe(networkError)
+  })
+
+  it('honours an external AbortSignal without labelling it a timeout', async () => {
+    const externalController = new AbortController()
+    globalThis.fetch = vi.fn().mockImplementation((_url, init?: RequestInit) => {
+      return new Promise((_resolve, reject) => {
+        init?.signal?.addEventListener('abort', () => {
+          const err = new Error('aborted by caller')
+          err.name = 'AbortError'
+          reject(err)
+        })
+      })
+    })
+
+    const promise = fetchWithTimeout(
+      'https://example.test/',
+      { method: 'POST', signal: externalController.signal },
+      { timeoutMs: 10_000, description: 'caller-cancelable fetch' },
+    )
+
+    externalController.abort()
+
+    await expect(promise).rejects.toSatisfy(
+      (err: unknown) =>
+        err instanceof Error &&
+        !(err instanceof TimeoutError) &&
+        err.name === 'AbortError',
+    )
+  })
+})
diff --git a/lib/http/fetch-with-timeout.ts b/lib/http/fetch-with-timeout.ts
new file mode 100644
index 00000000..861a8e5a
--- /dev/null
+++ b/lib/http/fetch-with-timeout.ts
@@ -0,0 +1,54 @@
+/**
+ * Thin `fetch` wrapper that aborts after a deadline.
+ *
+ * Used by OAuth token endpoints where a hung provider would otherwise hold
+ * the request thread indefinitely. The Skatteverket callback handler also
+ * relies on `TimeoutError` to distinguish a hung token exchange (where the
+ * 5-minute BankID auth code may expire mid-call) from other failures.
+ */
+
+export class TimeoutError extends Error {
+  readonly name = 'TimeoutError'
+}
+
+export function isTimeoutError(error: unknown): boolean {
+  return (
+    error instanceof Error &&
+    (error.name === 'TimeoutError' || error.name === 'AbortError')
+  )
+}
+
+export const OAUTH_TIMEOUT_MS = 10_000
+export const OAUTH_REVOKE_TIMEOUT_MS = 5_000
+export const SKATTEVERKET_EXCHANGE_TIMEOUT_MS = 8_000
+
+interface FetchWithTimeoutOptions {
+  timeoutMs: number
+  description: string
+}
+
+export async function fetchWithTimeout(
+  input: RequestInfo | URL,
+  init: RequestInit,
+  options: FetchWithTimeoutOptions,
+): Promise<Response> {
+  const { timeoutMs, description } = options
+
+  const timeoutSignal = AbortSignal.timeout(timeoutMs)
+  const signal = init.signal
+    ? AbortSignal.any([init.signal, timeoutSignal])
+    : timeoutSignal
+
+  try {
+    return await fetch(input, { ...init, signal })
+  } catch (err) {
+    if (
+      timeoutSignal.aborted &&
+      err instanceof Error &&
+      (err.name === 'TimeoutError' || err.name === 'AbortError')
+    ) {
+      throw new TimeoutError(`${description} timed out after ${timeoutMs}ms`)
+    }
+    throw err
+  }
+}
diff --git a/lib/providers/bjornlunden/client.ts b/lib/providers/bjornlunden/client.ts
index fc901ade..c62c2f8f 100644
--- a/lib/providers/bjornlunden/client.ts
+++ b/lib/providers/bjornlunden/client.ts
@@ -1,6 +1,9 @@
 import { TokenBucketRateLimiter } from '../rate-limiter';
 import { withRetry } from '../retry';
 import { BL_BASE_URL, BL_RATE_LIMIT } from './config';
+import { isTimeoutError } from '@/lib/http/fetch-with-timeout';
+
+const FETCH_TIMEOUT_MS = 15_000;
 
 export class BjornLundenApiError extends Error {
   constructor(
@@ -14,6 +17,7 @@ export class BjornLundenApiError extends Error {
 }
 
 function isRetryableError(error: unknown): boolean {
+  if (isTimeoutError(error)) return true;
   if (error instanceof BjornLundenApiError) {
     if (error.statusCode === 401 || error.statusCode === 403 || error.statusCode === 404) {
       return false;
@@ -50,6 +54,7 @@ export class BjornLundenClient {
             'User-Key': userKey,
             Accept: 'application/json',
           },
+          signal: AbortSignal.timeout(FETCH_TIMEOUT_MS),
         });
 
         if (!response.ok) {
diff --git a/lib/providers/bjornlunden/oauth.ts b/lib/providers/bjornlunden/oauth.ts
index 4f615a53..4974f936 100644
--- a/lib/providers/bjornlunden/oauth.ts
+++ b/lib/providers/bjornlunden/oauth.ts
@@ -1,4 +1,8 @@
 import type { TokenResponse } from '../types';
+import {
+  fetchWithTimeout,
+  OAUTH_TIMEOUT_MS,
+} from '@/lib/http/fetch-with-timeout';
 
 const BL_AUTH_URL = 'https://apigateway.blinfo.se/auth/oauth/v2/token';
 
@@ -6,17 +10,21 @@ export async function fetchBjornLundenToken(
   clientId: string,
   clientSecret: string,
 ): Promise<TokenResponse> {
-  const response = await fetch(BL_AUTH_URL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/x-www-form-urlencoded',
+  const response = await fetchWithTimeout(
+    BL_AUTH_URL,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+      },
+      body: new URLSearchParams({
+        grant_type: 'client_credentials',
+        client_id: clientId,
+        client_secret: clientSecret,
+      }).toString(),
     },
-    body: new URLSearchParams({
-      grant_type: 'client_credentials',
-      client_id: clientId,
-      client_secret: clientSecret,
-    }).toString(),
-  });
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Björn Lundén token request' },
+  );
 
   if (!response.ok) {
     const body = await response.text().catch(() => '');
diff --git a/lib/providers/bokio/client.ts b/lib/providers/bokio/client.ts
index 5dd53a32..609dd603 100644
--- a/lib/providers/bokio/client.ts
+++ b/lib/providers/bokio/client.ts
@@ -2,9 +2,12 @@ import { TokenBucketRateLimiter } from '../rate-limiter';
 import { withRetry } from '../retry';
 import { BOKIO_BASE_URL, BOKIO_RATE_LIMIT } from './config';
 import { createLogger } from '@/lib/logger';
+import { isTimeoutError } from '@/lib/http/fetch-with-timeout';
 
 const log = createLogger('bokio-client');
 
+const FETCH_TIMEOUT_MS = 15_000;
+
 export class BokioApiError extends Error {
   constructor(
     message: string,
@@ -17,6 +20,7 @@ export class BokioApiError extends Error {
 }
 
 function isRetryableError(error: unknown): boolean {
+  if (isTimeoutError(error)) return true;
   if (error instanceof BokioApiError) {
     if (error.statusCode === 401 || error.statusCode === 403 || error.statusCode === 404) {
       return false;
@@ -53,6 +57,7 @@ export class BokioClient {
             Authorization: `Bearer ${accessToken}`,
             Accept: 'application/json',
           },
+          signal: AbortSignal.timeout(FETCH_TIMEOUT_MS),
         });
 
         if (!response.ok) {
diff --git a/lib/providers/briox/client.ts b/lib/providers/briox/client.ts
index e6ce890f..0af04432 100644
--- a/lib/providers/briox/client.ts
+++ b/lib/providers/briox/client.ts
@@ -1,6 +1,9 @@
 import { TokenBucketRateLimiter } from '../rate-limiter';
 import { withRetry } from '../retry';
 import { BRIOX_BASE_URL, BRIOX_RATE_LIMIT } from './config';
+import { isTimeoutError } from '@/lib/http/fetch-with-timeout';
+
+const FETCH_TIMEOUT_MS = 15_000;
 
 export class BrioxApiError extends Error {
   constructor(
@@ -14,6 +17,7 @@ export class BrioxApiError extends Error {
 }
 
 function isRetryableError(error: unknown): boolean {
+  if (isTimeoutError(error)) return true;
   if (error instanceof BrioxApiError) {
     if (error.statusCode === 401 || error.statusCode === 403 || error.statusCode === 404) {
       return false;
@@ -53,6 +57,7 @@ export class BrioxClient {
             Accept: 'application/json',
             'Content-Type': 'application/json',
           },
+          signal: AbortSignal.timeout(FETCH_TIMEOUT_MS),
         });
 
         if (!response.ok) {
diff --git a/lib/providers/briox/oauth.ts b/lib/providers/briox/oauth.ts
index 2081abf5..dbd2ce65 100644
--- a/lib/providers/briox/oauth.ts
+++ b/lib/providers/briox/oauth.ts
@@ -1,5 +1,9 @@
 import { BRIOX_TOKEN_URL, BRIOX_REFRESH_URL } from './config';
 import type { TokenResponse } from '../types';
+import {
+  fetchWithTimeout,
+  OAUTH_TIMEOUT_MS,
+} from '@/lib/http/fetch-with-timeout';
 
 interface BrioxTokenData {
   access_token: string;
@@ -29,12 +33,16 @@ export async function exchangeBrioxCode(
 ): Promise<TokenResponse> {
   const url = `${BRIOX_TOKEN_URL}?clientid=${encodeURIComponent(clientId)}&token=${encodeURIComponent(applicationToken)}`;
 
-  const response = await fetch(url, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/json',
+  const response = await fetchWithTimeout(
+    url,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
     },
-  });
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Briox token exchange' },
+  );
 
   if (!response.ok) {
     const body = await response.text().catch(() => '');
@@ -51,12 +59,16 @@ export async function refreshBrioxToken(
 ): Promise<TokenResponse> {
   const url = `${BRIOX_REFRESH_URL}?refreshtoken=${encodeURIComponent(refreshToken)}&token=${encodeURIComponent(refreshToken)}`;
 
-  const response = await fetch(url, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/json',
+  const response = await fetchWithTimeout(
+    url,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
     },
-  });
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Briox token refresh' },
+  );
 
   if (!response.ok) {
     const body = await response.text().catch(() => '');
diff --git a/lib/providers/fortnox/client.ts b/lib/providers/fortnox/client.ts
index 9e2109b6..853a4aaf 100644
--- a/lib/providers/fortnox/client.ts
+++ b/lib/providers/fortnox/client.ts
@@ -1,6 +1,9 @@
 import { TokenBucketRateLimiter } from '../rate-limiter';
 import { withRetry } from '../retry';
 import { FORTNOX_BASE_URL, FORTNOX_RATE_LIMIT } from './config';
+import { isTimeoutError } from '@/lib/http/fetch-with-timeout';
+
+const FETCH_TIMEOUT_MS = 15_000;
 
 export class FortnoxApiError extends Error {
   constructor(
@@ -15,6 +18,7 @@ export class FortnoxApiError extends Error {
 }
 
 function isRetryableError(error: unknown): boolean {
+  if (isTimeoutError(error)) return true;
   if (error instanceof FortnoxApiError) {
     if (error.statusCode === 401 || error.statusCode === 403 || error.statusCode === 404) {
       return false;
@@ -44,6 +48,7 @@ export class FortnoxClient {
             Accept: 'application/json',
             'Content-Type': 'application/json',
           },
+          signal: AbortSignal.timeout(FETCH_TIMEOUT_MS),
         });
 
         if (!response.ok) {
@@ -87,6 +92,7 @@ export class FortnoxClient {
           headers: {
             Authorization: `Bearer ${accessToken}`,
           },
+          signal: AbortSignal.timeout(FETCH_TIMEOUT_MS),
         });
 
         if (!response.ok) {
diff --git a/lib/providers/fortnox/oauth.ts b/lib/providers/fortnox/oauth.ts
index af333ed1..5ed08a3f 100644
--- a/lib/providers/fortnox/oauth.ts
+++ b/lib/providers/fortnox/oauth.ts
@@ -1,5 +1,10 @@
 import { FORTNOX_AUTH_URL, FORTNOX_TOKEN_URL } from './config';
 import type { OAuthConfig, TokenResponse } from '../types';
+import {
+  fetchWithTimeout,
+  OAUTH_TIMEOUT_MS,
+  OAUTH_REVOKE_TIMEOUT_MS,
+} from '@/lib/http/fetch-with-timeout';
 
 const DEFAULT_SCOPES = [
   'companyinformation',
@@ -40,18 +45,22 @@ export async function exchangeFortnoxCode(
   config: OAuthConfig,
   code: string,
 ): Promise<TokenResponse> {
-  const response = await fetch(FORTNOX_TOKEN_URL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/x-www-form-urlencoded',
-      Authorization: basicAuthHeader(config),
+  const response = await fetchWithTimeout(
+    FORTNOX_TOKEN_URL,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Authorization: basicAuthHeader(config),
+      },
+      body: new URLSearchParams({
+        grant_type: 'authorization_code',
+        code,
+        redirect_uri: config.redirectUri,
+      }).toString(),
     },
-    body: new URLSearchParams({
-      grant_type: 'authorization_code',
-      code,
-      redirect_uri: config.redirectUri,
-    }).toString(),
-  });
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Fortnox token exchange' },
+  );
 
   if (!response.ok) {
     const body = await response.text().catch(() => '');
@@ -65,17 +74,21 @@ export async function refreshFortnoxToken(
   config: OAuthConfig,
   refreshToken: string,
 ): Promise<TokenResponse> {
-  const response = await fetch(FORTNOX_TOKEN_URL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/x-www-form-urlencoded',
-      Authorization: basicAuthHeader(config),
+  const response = await fetchWithTimeout(
+    FORTNOX_TOKEN_URL,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Authorization: basicAuthHeader(config),
+      },
+      body: new URLSearchParams({
+        grant_type: 'refresh_token',
+        refresh_token: refreshToken,
+      }).toString(),
     },
-    body: new URLSearchParams({
-      grant_type: 'refresh_token',
-      refresh_token: refreshToken,
-    }).toString(),
-  });
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Fortnox token refresh' },
+  );
 
   if (!response.ok) {
     const body = await response.text().catch(() => '');
@@ -89,17 +102,21 @@ export async function revokeFortnoxToken(
   config: OAuthConfig,
   refreshToken: string,
 ): Promise<boolean> {
-  const response = await fetch(FORTNOX_TOKEN_URL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/x-www-form-urlencoded',
-      Authorization: basicAuthHeader(config),
+  const response = await fetchWithTimeout(
+    FORTNOX_TOKEN_URL,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Authorization: basicAuthHeader(config),
+      },
+      body: new URLSearchParams({
+        token: refreshToken,
+        token_type_hint: 'refresh_token',
+      }).toString(),
     },
-    body: new URLSearchParams({
-      token: refreshToken,
-      token_type_hint: 'refresh_token',
-    }).toString(),
-  });
+    { timeoutMs: OAUTH_REVOKE_TIMEOUT_MS, description: 'Fortnox token revoke' },
+  );
 
   return response.ok;
 }
diff --git a/lib/providers/visma/client.ts b/lib/providers/visma/client.ts
index 8a71a571..e82a455e 100644
--- a/lib/providers/visma/client.ts
+++ b/lib/providers/visma/client.ts
@@ -1,6 +1,9 @@
 import { TokenBucketRateLimiter } from '../rate-limiter';
 import { withRetry } from '../retry';
 import { VISMA_BASE_URL, VISMA_RATE_LIMIT } from './config';
+import { isTimeoutError } from '@/lib/http/fetch-with-timeout';
+
+const FETCH_TIMEOUT_MS = 15_000;
 
 export class VismaApiError extends Error {
   constructor(
@@ -14,6 +17,7 @@ export class VismaApiError extends Error {
 }
 
 function isRetryableError(error: unknown): boolean {
+  if (isTimeoutError(error)) return true;
   if (error instanceof VismaApiError) {
     if (error.statusCode === 401 || error.statusCode === 403 || error.statusCode === 404) {
       return false;
@@ -48,6 +52,7 @@ export class VismaClient {
             Accept: 'application/json',
             'Content-Type': 'application/json',
           },
+          signal: AbortSignal.timeout(FETCH_TIMEOUT_MS),
         });
 
         if (!response.ok) {
diff --git a/lib/providers/visma/oauth.ts b/lib/providers/visma/oauth.ts
index 7f7899f4..34b8d260 100644
--- a/lib/providers/visma/oauth.ts
+++ b/lib/providers/visma/oauth.ts
@@ -1,5 +1,10 @@
 import { VISMA_AUTH_URL, VISMA_TOKEN_URL, VISMA_REVOKE_URL } from './config';
 import type { OAuthConfig, TokenResponse } from '../types';
+import {
+  fetchWithTimeout,
+  OAUTH_TIMEOUT_MS,
+  OAUTH_REVOKE_TIMEOUT_MS,
+} from '@/lib/http/fetch-with-timeout';
 
 const DEFAULT_SCOPES = [
   'ea:api',
@@ -41,18 +46,22 @@ export async function exchangeVismaCode(
   config: OAuthConfig,
   code: string,
 ): Promise<TokenResponse> {
-  const response = await fetch(VISMA_TOKEN_URL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/x-www-form-urlencoded',
-      Authorization: basicAuthHeader(config),
+  const response = await fetchWithTimeout(
+    VISMA_TOKEN_URL,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Authorization: basicAuthHeader(config),
+      },
+      body: new URLSearchParams({
+        grant_type: 'authorization_code',
+        code,
+        redirect_uri: config.redirectUri,
+      }).toString(),
     },
-    body: new URLSearchParams({
-      grant_type: 'authorization_code',
-      code,
-      redirect_uri: config.redirectUri,
-    }).toString(),
-  });
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Visma token exchange' },
+  );
 
   if (!response.ok) {
     const body = await response.text().catch(() => '');
@@ -66,17 +75,21 @@ export async function refreshVismaToken(
   config: OAuthConfig,
   refreshToken: string,
 ): Promise<TokenResponse> {
-  const response = await fetch(VISMA_TOKEN_URL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/x-www-form-urlencoded',
-      Authorization: basicAuthHeader(config),
+  const response = await fetchWithTimeout(
+    VISMA_TOKEN_URL,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Authorization: basicAuthHeader(config),
+      },
+      body: new URLSearchParams({
+        grant_type: 'refresh_token',
+        refresh_token: refreshToken,
+      }).toString(),
     },
-    body: new URLSearchParams({
-      grant_type: 'refresh_token',
-      refresh_token: refreshToken,
-    }).toString(),
-  });
+    { timeoutMs: OAUTH_TIMEOUT_MS, description: 'Visma token refresh' },
+  );
 
   if (!response.ok) {
     const body = await response.text().catch(() => '');
@@ -90,17 +103,21 @@ export async function revokeVismaToken(
   config: OAuthConfig,
   refreshToken: string,
 ): Promise<boolean> {
-  const response = await fetch(VISMA_REVOKE_URL, {
-    method: 'POST',
-    headers: {
-      'Content-Type': 'application/x-www-form-urlencoded',
-      Authorization: basicAuthHeader(config),
+  const response = await fetchWithTimeout(
+    VISMA_REVOKE_URL,
+    {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/x-www-form-urlencoded',
+        Authorization: basicAuthHeader(config),
+      },
+      body: new URLSearchParams({
+        token: refreshToken,
+        token_type_hint: 'refresh_token',
+      }).toString(),
     },
-    body: new URLSearchParams({
-      token: refreshToken,
-      token_type_hint: 'refresh_token',
-    }).toString(),
-  });
+    { timeoutMs: OAUTH_REVOKE_TIMEOUT_MS, description: 'Visma token revoke' },
+  );
 
   return response.ok;
 }
diff --git a/supabase/migrations/20260421160000_booking_template_usage.sql b/supabase/migrations/20260421160000_booking_template_usage.sql
index f14e1e5b..f10f839d 100644
--- a/supabase/migrations/20260421160000_booking_template_usage.sql
+++ b/supabase/migrations/20260421160000_booking_template_usage.sql
@@ -12,7 +12,7 @@
 --
 -- One row per (template_id, company_id). Upsert on use.
 
-CREATE TABLE public.booking_template_usage (
+CREATE TABLE IF NOT EXISTS public.booking_template_usage (
   id              UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
   template_id     UUID NOT NULL REFERENCES public.booking_template_library(id) ON DELETE CASCADE,
   company_id      UUID NOT NULL REFERENCES public.companies(id) ON DELETE CASCADE,
@@ -25,28 +25,32 @@ CREATE TABLE public.booking_template_usage (
 -- RLS
 ALTER TABLE public.booking_template_usage ENABLE ROW LEVEL SECURITY;
 
+DROP POLICY IF EXISTS "btu_select" ON public.booking_template_usage;
 CREATE POLICY "btu_select" ON public.booking_template_usage
   FOR SELECT USING (
     company_id IN (SELECT public.user_company_ids())
   );
 
+DROP POLICY IF EXISTS "btu_insert" ON public.booking_template_usage;
 CREATE POLICY "btu_insert" ON public.booking_template_usage
   FOR INSERT WITH CHECK (
     company_id IN (SELECT public.user_company_ids())
   );
 
+DROP POLICY IF EXISTS "btu_update" ON public.booking_template_usage;
 CREATE POLICY "btu_update" ON public.booking_template_usage
   FOR UPDATE USING (
     company_id IN (SELECT public.user_company_ids())
   );
 
+DROP POLICY IF EXISTS "btu_delete" ON public.booking_template_usage;
 CREATE POLICY "btu_delete" ON public.booking_template_usage
   FOR DELETE USING (
     company_id IN (SELECT public.user_company_ids())
   );
 
 -- Index for the sort query: fetch last_used_at for a given company.
-CREATE INDEX idx_btu_company_last_used
+CREATE INDEX IF NOT EXISTS idx_btu_company_last_used
   ON public.booking_template_usage (company_id, last_used_at DESC);
 
 -- Schema reload for PostgREST
diff --git a/supabase/migrations/20260421160000_opening_balances_rpc.sql b/supabase/migrations/20260421160500_opening_balances_rpc.sql
similarity index 100%
rename from supabase/migrations/20260421160000_opening_balances_rpc.sql
rename to supabase/migrations/20260421160500_opening_balances_rpc.sql
diff --git a/supabase/migrations/20260421170000_commit_journal_entry_user_id_fallback.sql b/supabase/migrations/20260421170500_commit_journal_entry_user_id_fallback.sql
similarity index 100%
rename from supabase/migrations/20260421170000_commit_journal_entry_user_id_fallback.sql
rename to supabase/migrations/20260421170500_commit_journal_entry_user_id_fallback.sql
diff --git a/supabase/migrations/20260422120000_fix_rls_role_gates_on_membership_tables.sql b/supabase/migrations/20260422120000_fix_rls_role_gates_on_membership_tables.sql
new file mode 100644
index 00000000..b276b9d9
--- /dev/null
+++ b/supabase/migrations/20260422120000_fix_rls_role_gates_on_membership_tables.sql
@@ -0,0 +1,265 @@
+-- =============================================================================
+-- Fix RLS escalation across multi-tenant authorization layer.
+--
+-- The INSERT/UPDATE/DELETE policies defined in
+--   20260330130000_multi_tenant_company_refactor.sql
+--   20260330140000_company_invitations.sql
+--   20260331010000_teams_table_refactor.sql
+-- gated writes only on `user_company_ids()` / `user_team_ids()` — i.e. any
+-- membership regardless of role. This allowed a user with role='viewer' to
+-- issue a direct PATCH against PostgREST and promote themselves to 'owner'
+-- (confirmed in production), bypassing the app-layer requireWritePermission
+-- guard entirely.
+--
+-- Fix: require the caller to hold role IN ('owner','admin') in the target
+-- company/team for every write on the authorization-sensitive tables. All
+-- legitimate app flows write via service role or SECURITY DEFINER RPCs/
+-- triggers, which bypass RLS — so these tightened policies only block
+-- direct PostgREST calls from user sessions, which was the exploit path.
+--
+-- Role check is wrapped in SECURITY DEFINER helpers (user_is_company_admin,
+-- user_is_team_admin) matching the existing user_company_ids() pattern.
+-- This is necessary because inlining `EXISTS (SELECT ... FROM company_members)`
+-- inside a policy ON company_members is detected by Postgres as recursive.
+-- SECURITY DEFINER functions bypass RLS internally, breaking the cycle.
+--
+-- Additionally: a BEFORE UPDATE trigger on company_members blocks any role
+-- change unless the caller already holds role='owner'. This reserves
+-- promotion to 'owner' (or demotion of one) to existing owners — admins
+-- cannot mint further owners even though they can otherwise write.
+-- =============================================================================
+
+-- =============================================================================
+-- 1. SECURITY DEFINER helper functions
+-- =============================================================================
+
+CREATE OR REPLACE FUNCTION public.user_is_company_admin(p_company_id uuid)
+RETURNS boolean
+LANGUAGE sql
+STABLE
+SECURITY DEFINER
+SET search_path = public
+AS $$
+  SELECT EXISTS (
+    SELECT 1 FROM public.company_members cm
+    WHERE cm.company_id = p_company_id
+      AND cm.user_id = auth.uid()
+      AND cm.role IN ('owner', 'admin')
+  );
+$$;
+
+GRANT EXECUTE ON FUNCTION public.user_is_company_admin(uuid) TO authenticated;
+
+CREATE OR REPLACE FUNCTION public.user_is_team_admin(p_team_id uuid)
+RETURNS boolean
+LANGUAGE sql
+STABLE
+SECURITY DEFINER
+SET search_path = public
+AS $$
+  SELECT EXISTS (
+    SELECT 1 FROM public.team_members tm
+    WHERE tm.team_id = p_team_id
+      AND tm.user_id = auth.uid()
+      AND tm.role IN ('owner', 'admin')
+  ) OR EXISTS (
+    SELECT 1 FROM public.teams t
+    WHERE t.id = p_team_id
+      AND t.created_by = auth.uid()
+  );
+$$;
+
+GRANT EXECUTE ON FUNCTION public.user_is_team_admin(uuid) TO authenticated;
+
+CREATE OR REPLACE FUNCTION public.user_role_in_company(p_company_id uuid)
+RETURNS text
+LANGUAGE sql
+STABLE
+SECURITY DEFINER
+SET search_path = public
+AS $$
+  SELECT role FROM public.company_members
+  WHERE company_id = p_company_id AND user_id = auth.uid();
+$$;
+
+GRANT EXECUTE ON FUNCTION public.user_role_in_company(uuid) TO authenticated;
+
+-- =============================================================================
+-- 2. company_members — tighten write policies
+-- =============================================================================
+
+DROP POLICY IF EXISTS "company_members_insert" ON public.company_members;
+DROP POLICY IF EXISTS "company_members_update" ON public.company_members;
+DROP POLICY IF EXISTS "company_members_delete" ON public.company_members;
+
+CREATE POLICY "company_members_insert" ON public.company_members
+  FOR INSERT WITH CHECK (public.user_is_company_admin(company_id));
+
+CREATE POLICY "company_members_update" ON public.company_members
+  FOR UPDATE
+  USING (public.user_is_company_admin(company_id))
+  WITH CHECK (public.user_is_company_admin(company_id));
+
+CREATE POLICY "company_members_delete" ON public.company_members
+  FOR DELETE USING (public.user_is_company_admin(company_id));
+
+-- =============================================================================
+-- 3. team_members — tighten write policies
+-- =============================================================================
+
+DROP POLICY IF EXISTS "team_members_insert" ON public.team_members;
+DROP POLICY IF EXISTS "team_members_update" ON public.team_members;
+DROP POLICY IF EXISTS "team_members_delete" ON public.team_members;
+
+CREATE POLICY "team_members_insert" ON public.team_members
+  FOR INSERT WITH CHECK (public.user_is_team_admin(team_id));
+
+CREATE POLICY "team_members_update" ON public.team_members
+  FOR UPDATE
+  USING (public.user_is_team_admin(team_id))
+  WITH CHECK (public.user_is_team_admin(team_id));
+
+CREATE POLICY "team_members_delete" ON public.team_members
+  FOR DELETE USING (public.user_is_team_admin(team_id));
+
+-- =============================================================================
+-- 4. api_keys — tighten write policies
+-- A viewer minting an API key with broad scopes is catastrophic.
+-- =============================================================================
+
+DROP POLICY IF EXISTS "api_keys_insert" ON public.api_keys;
+DROP POLICY IF EXISTS "api_keys_update" ON public.api_keys;
+DROP POLICY IF EXISTS "api_keys_delete" ON public.api_keys;
+
+CREATE POLICY "api_keys_insert" ON public.api_keys
+  FOR INSERT WITH CHECK (public.user_is_company_admin(company_id));
+
+CREATE POLICY "api_keys_update" ON public.api_keys
+  FOR UPDATE
+  USING (public.user_is_company_admin(company_id))
+  WITH CHECK (public.user_is_company_admin(company_id));
+
+CREATE POLICY "api_keys_delete" ON public.api_keys
+  FOR DELETE USING (public.user_is_company_admin(company_id));
+
+-- =============================================================================
+-- 5. company_invitations — tighten write policies
+-- =============================================================================
+
+DROP POLICY IF EXISTS "company_invitations_insert" ON public.company_invitations;
+DROP POLICY IF EXISTS "company_invitations_update" ON public.company_invitations;
+DROP POLICY IF EXISTS "company_invitations_delete" ON public.company_invitations;
+
+CREATE POLICY "company_invitations_insert" ON public.company_invitations
+  FOR INSERT WITH CHECK (public.user_is_company_admin(company_id));
+
+CREATE POLICY "company_invitations_update" ON public.company_invitations
+  FOR UPDATE
+  USING (public.user_is_company_admin(company_id))
+  WITH CHECK (public.user_is_company_admin(company_id));
+
+CREATE POLICY "company_invitations_delete" ON public.company_invitations
+  FOR DELETE USING (public.user_is_company_admin(company_id));
+
+-- =============================================================================
+-- 6. team_invitations — tighten write policies
+-- =============================================================================
+
+DROP POLICY IF EXISTS "team_invitations_insert" ON public.team_invitations;
+DROP POLICY IF EXISTS "team_invitations_update" ON public.team_invitations;
+DROP POLICY IF EXISTS "team_invitations_delete" ON public.team_invitations;
+
+CREATE POLICY "team_invitations_insert" ON public.team_invitations
+  FOR INSERT WITH CHECK (public.user_is_team_admin(team_id));
+
+CREATE POLICY "team_invitations_update" ON public.team_invitations
+  FOR UPDATE
+  USING (public.user_is_team_admin(team_id))
+  WITH CHECK (public.user_is_team_admin(team_id));
+
+CREATE POLICY "team_invitations_delete" ON public.team_invitations
+  FOR DELETE USING (public.user_is_team_admin(team_id));
+
+-- =============================================================================
+-- 7. companies — tighten UPDATE policy (INSERT keeps created_by check)
+-- =============================================================================
+
+DROP POLICY IF EXISTS "companies_update" ON public.companies;
+
+CREATE POLICY "companies_update" ON public.companies
+  FOR UPDATE
+  USING (public.user_is_company_admin(id))
+  WITH CHECK (public.user_is_company_admin(id));
+
+-- =============================================================================
+-- 8. teams — tighten UPDATE policy (INSERT keeps created_by check)
+-- =============================================================================
+
+DROP POLICY IF EXISTS "teams_update" ON public.teams;
+
+CREATE POLICY "teams_update" ON public.teams
+  FOR UPDATE
+  USING (public.user_is_team_admin(id) OR created_by = auth.uid())
+  WITH CHECK (public.user_is_team_admin(id) OR created_by = auth.uid());
+
+-- =============================================================================
+-- 9. company_settings — tighten write policies
+-- =============================================================================
+
+DROP POLICY IF EXISTS "company_settings_insert" ON public.company_settings;
+DROP POLICY IF EXISTS "company_settings_update" ON public.company_settings;
+
+CREATE POLICY "company_settings_insert" ON public.company_settings
+  FOR INSERT WITH CHECK (public.user_is_company_admin(company_id));
+
+CREATE POLICY "company_settings_update" ON public.company_settings
+  FOR UPDATE
+  USING (public.user_is_company_admin(company_id))
+  WITH CHECK (public.user_is_company_admin(company_id));
+
+-- =============================================================================
+-- 10. BEFORE UPDATE trigger on company_members:
+--     block role transitions unless the caller already holds role='owner'.
+-- Service role / SECURITY DEFINER / direct SQL (migration apply) pass through
+-- because auth.uid() is NULL in those contexts.
+-- =============================================================================
+
+CREATE OR REPLACE FUNCTION public.enforce_company_member_role_transitions()
+RETURNS trigger
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  caller_role text;
+BEGIN
+  -- Service role, SECURITY DEFINER cascades, and direct SQL have no auth context.
+  IF auth.uid() IS NULL THEN
+    RETURN NEW;
+  END IF;
+
+  -- Nothing to enforce if the role field isn't changing.
+  IF NEW.role IS NOT DISTINCT FROM OLD.role THEN
+    RETURN NEW;
+  END IF;
+
+  caller_role := public.user_role_in_company(OLD.company_id);
+
+  IF caller_role IS DISTINCT FROM 'owner' THEN
+    RAISE EXCEPTION
+      'Only owners can change member roles (your role: %)',
+      COALESCE(caller_role, 'none');
+  END IF;
+
+  RETURN NEW;
+END;
+$$;
+
+DROP TRIGGER IF EXISTS enforce_company_member_role_transitions
+  ON public.company_members;
+
+CREATE TRIGGER enforce_company_member_role_transitions
+  BEFORE UPDATE ON public.company_members
+  FOR EACH ROW
+  EXECUTE FUNCTION public.enforce_company_member_role_transitions();
+
+-- Force PostgREST to pick up the new policies immediately.
+NOTIFY pgrst, 'reload schema';
diff --git a/supabase/migrations/20260422130000_close_company_members_insert_role_bypass.sql b/supabase/migrations/20260422130000_close_company_members_insert_role_bypass.sql
new file mode 100644
index 00000000..15355116
--- /dev/null
+++ b/supabase/migrations/20260422130000_close_company_members_insert_role_bypass.sql
@@ -0,0 +1,80 @@
+-- =============================================================================
+-- Close INSERT bypass in company_members owner-role guard.
+--
+-- 20260422120000_fix_rls_role_gates_on_membership_tables.sql added a
+-- BEFORE UPDATE trigger that blocks non-owners from promoting members to
+-- role='owner'. The trigger fires only on UPDATE, and the INSERT policy
+-- (company_members_insert) passes any caller with role IN ('owner','admin')
+-- with no constraint on NEW.role. An admin could therefore bypass the guard
+-- entirely via a direct PostgREST INSERT with role='owner', contradicting
+-- the stated guarantee that only owners can mint further owners.
+--
+-- Fix: add a BEFORE INSERT trigger that blocks role='owner' unless the
+-- caller already holds role='owner' in the target company.
+--
+-- Bootstrap case: create_company_with_owner() (SECURITY DEFINER RPC)
+-- preserves auth.uid() while inserting the first owner membership for a
+-- freshly created company. The trigger must allow this path. The helper
+-- user_role_in_company() returns NULL at that moment (no prior membership),
+-- so we permit the insert when (a) the caller is inserting themselves and
+-- (b) the company has no existing owner. Both conditions together pin the
+-- escape hatch to genuine first-time bootstrap; a subsequent attempt to
+-- inject a second owner fails on condition (b).
+-- =============================================================================
+
+CREATE OR REPLACE FUNCTION public.enforce_company_member_role_on_insert()
+RETURNS trigger
+LANGUAGE plpgsql
+AS $$
+DECLARE
+  caller_role text;
+BEGIN
+  -- Service role and direct SQL (migration apply, admin console) have no
+  -- auth context; pass through unchanged.
+  IF auth.uid() IS NULL THEN
+    RETURN NEW;
+  END IF;
+
+  -- Only the 'owner' role is gated; admin/member/viewer pass through so that
+  -- admins retain the ability to add non-owner members.
+  IF NEW.role IS DISTINCT FROM 'owner' THEN
+    RETURN NEW;
+  END IF;
+
+  caller_role := public.user_role_in_company(NEW.company_id);
+
+  -- Existing owners can always mint owners.
+  IF caller_role = 'owner' THEN
+    RETURN NEW;
+  END IF;
+
+  -- Bootstrap: create_company_with_owner RPC inserts the first owner
+  -- membership. The caller has no prior membership (caller_role IS NULL)
+  -- and inserts themselves. Reject if an owner already exists to prevent
+  -- this path from being reused to mint a second owner.
+  IF caller_role IS NULL
+     AND NEW.user_id = auth.uid()
+     AND NOT EXISTS (
+       SELECT 1 FROM public.company_members
+       WHERE company_id = NEW.company_id
+         AND role = 'owner'
+     )
+  THEN
+    RETURN NEW;
+  END IF;
+
+  RAISE EXCEPTION
+    'Only owners can add members with role ''owner'' (your role: %)',
+    COALESCE(caller_role, 'none');
+END;
+$$;
+
+DROP TRIGGER IF EXISTS enforce_company_member_role_on_insert
+  ON public.company_members;
+
+CREATE TRIGGER enforce_company_member_role_on_insert
+  BEFORE INSERT ON public.company_members
+  FOR EACH ROW
+  EXECUTE FUNCTION public.enforce_company_member_role_on_insert();
+
+NOTIFY pgrst, 'reload schema';