diff --git a/changelog.d/2-features/blacklist-change-phone b/changelog.d/2-features/blacklist-change-phone
new file mode 100644
index 0000000000..1a01f3cf73
--- /dev/null
+++ b/changelog.d/2-features/blacklist-change-phone
@@ -0,0 +1 @@
+Disallow changing phone number to a black listed phone number
\ No newline at end of file
diff --git a/services/brig/src/Brig/API/Error.hs b/services/brig/src/Brig/API/Error.hs
index af50a8a7f1..c30b4fb5d7 100644
--- a/services/brig/src/Brig/API/Error.hs
+++ b/services/brig/src/Brig/API/Error.hs
@@ -144,6 +144,7 @@ changeEmailError EmailManagedByScim = StdError $ propertyManagedByScim "email"
 changePhoneError :: ChangePhoneError -> Error
 changePhoneError (InvalidNewPhone _) = StdError invalidPhone
 changePhoneError (PhoneExists _) = StdError userKeyExists
+changePhoneError (BlacklistedNewPhone _) = StdError blacklistedPhone
 
 changePwError :: ChangePasswordError -> Error
 changePwError InvalidCurrentPassword = StdError badCredentials
diff --git a/services/brig/src/Brig/API/Types.hs b/services/brig/src/Brig/API/Types.hs
index 8241149efb..61179203f4 100644
--- a/services/brig/src/Brig/API/Types.hs
+++ b/services/brig/src/Brig/API/Types.hs
@@ -165,6 +165,7 @@ data ChangePasswordError
 data ChangePhoneError
   = PhoneExists !Phone
   | InvalidNewPhone !Phone
+  | BlacklistedNewPhone !Phone
 
 data ChangeEmailError
   = InvalidNewEmail !Email !String
diff --git a/services/brig/src/Brig/API/User.hs b/services/brig/src/Brig/API/User.hs
index 544da73726..fe6bf6d931 100644
--- a/services/brig/src/Brig/API/User.hs
+++ b/services/brig/src/Brig/API/User.hs
@@ -604,19 +604,26 @@ changeEmail u email allowScim = do
 
 changePhone :: UserId -> Phone -> ExceptT ChangePhoneError AppIO (Activation, Phone)
 changePhone u phone = do
-  ph <-
+  canonical <-
     maybe
       (throwE $ InvalidNewPhone phone)
       return
       =<< lift (validatePhone phone)
-  let pk = userPhoneKey ph
+  let pk = userPhoneKey canonical
   available <- lift $ Data.keyAvailable pk (Just u)
   unless available $
     throwE $
       PhoneExists phone
   timeout <- setActivationTimeout <$> view settings
+  blacklisted <- lift $ Blacklist.exists pk
+  when blacklisted $
+    throwE (BlacklistedNewPhone canonical)
+  -- check if any prefixes of this phone number are blocked
+  prefixExcluded <- lift $ Blacklist.existsAnyPrefix canonical
+  when prefixExcluded $
+    throwE (BlacklistedNewPhone canonical)
   act <- lift $ Data.newActivation pk timeout (Just u)
-  return (act, ph)
+  return (act, canonical)
 
 -------------------------------------------------------------------------------
 -- Remove Email
diff --git a/services/brig/test/integration/API/User/Account.hs b/services/brig/test/integration/API/User/Account.hs
index f687f1b3de..a7a4de6b24 100644
--- a/services/brig/test/integration/API/User/Account.hs
+++ b/services/brig/test/integration/API/User/Account.hs
@@ -105,6 +105,7 @@ tests _ at opts p b c ch g aws =
       test' aws p "put /self - 200" $ testUserUpdate b c aws,
       test' aws p "put /access/self/email - 2xx" $ testEmailUpdate b aws,
       test' aws p "put /self/phone - 202" $ testPhoneUpdate b,
+      test' aws p "put /self/phone - 403" $ testPhoneUpdateBlacklisted b,
       test' aws p "head /self/password - 200/404" $ testPasswordSet b,
       test' aws p "put /self/password - 200" $ testPasswordChange b,
       test' aws p "put /self/locale - 200" $ testUserLocaleUpdate b aws,
@@ -762,6 +763,22 @@ testPhoneUpdate brig = do
     const 200 === statusCode
     const (Just phn) === (userPhone <=< responseJsonMaybe)
 
+testPhoneUpdateBlacklisted :: Brig -> Http ()
+testPhoneUpdateBlacklisted brig = do
+  uid <- userId <$> randomUser brig
+  phn <- randomPhone
+  let prefix = mkPrefix $ T.take 5 (fromPhone phn)
+
+  insertPrefix brig prefix
+  let phoneUpdate = RequestBodyLBS . encode $ PhoneUpdate phn
+  put (brig . path "/self/phone" . contentJson . zUser uid . zConn "c" . body phoneUpdate)
+    !!! (const 403 === statusCode)
+
+  -- check that phone is not updated
+  get (brig . path "/self" . zUser uid) !!! do
+    const 200 === statusCode
+    const (Right Nothing) === fmap userPhone . responseJsonEither
+
 testCreateAccountPendingActivationKey :: Opt.Opts -> Brig -> Http ()
 testCreateAccountPendingActivationKey (Opt.setRestrictUserCreation . Opt.optSettings -> Just True) _ = pure ()
 testCreateAccountPendingActivationKey _ brig = do