diff --git a/jmclient/jmclient/wallet.py b/jmclient/jmclient/wallet.py
index c9b2dc8..59c581a 100644
--- a/jmclient/jmclient/wallet.py
+++ b/jmclient/jmclient/wallet.py
@@ -1245,7 +1245,11 @@ class BIP39WalletMixin(object):
             storage, network, max_mixdepth, timestamp, entropy,
             write=False, **kwargs)
         if entropy_extension:
-            storage.data[cls._BIP39_EXTENSION_KEY] = entropy_extension
+            # Note: future reads from storage will retrieve this data
+            # as binary, so set it as binary on initialization for consistency.
+            # Note that this is in contrast to the mnemonic wordlist, which is
+            # handled by the mnemonic package, which returns the words as a string.
+            storage.data[cls._BIP39_EXTENSION_KEY] = entropy_extension.encode("utf-8")
 
         if write:
             storage.save()
diff --git a/jmclient/jmclient/wallet_utils.py b/jmclient/jmclient/wallet_utils.py
index e080a11..6770a9e 100644
--- a/jmclient/jmclient/wallet_utils.py
+++ b/jmclient/jmclient/wallet_utils.py
@@ -562,7 +562,8 @@ def cli_get_wallet_file_name(defaultname="wallet.jmdat"):
 def cli_display_user_words(words, mnemonic_extension):
     text = 'Write down this wallet recovery mnemonic\n\n' + words +'\n'
     if mnemonic_extension:
-        text += '\nAnd this mnemonic extension: ' + mnemonic_extension + '\n'
+        text += '\nAnd this mnemonic extension: ' + mnemonic_extension.decode(
+            'utf-8') + '\n'
     jmprint(text, "important")
 
 def cli_user_mnemonic_entry():