diff --git a/electrum/plugins/bitbox02/bitbox02.py b/electrum/plugins/bitbox02/bitbox02.py
index 8f720e5f6..50f2e9115 100644
--- a/electrum/plugins/bitbox02/bitbox02.py
+++ b/electrum/plugins/bitbox02/bitbox02.py
@@ -577,6 +577,10 @@ class BitBox02_KeyStore(Hardware_KeyStore):
         )
 
     def sign_message(self, sequence, message, password, *, script_type=None):
+        if constants.net.TESTNET:
+            raise UserFacingException(
+                _("The {} only supports message signing on mainnet.").format(self.device)
+            )
         if password:
             raise Exception("BitBox02 does not accept a password from the host")
         client = self.get_client()