diff --git a/helios/crypto/utils.py b/helios/crypto/utils.py
index d854c886bd6e6a0128fbdeec232305ee97870a2a..2fcce307f37bc81f0727f851c7ecbdaa60ace05c 100644
--- a/helios/crypto/utils.py
+++ b/helios/crypto/utils.py
@@ -27,5 +27,5 @@ def hash_b64(s):
     removes the trailing "="
     """
     hasher = SHA256.new(s.encode('utf-8'))
-    result = base64.b64encode(hasher.digest())[:-1]
+    result = base64.b64encode(hasher.digest())[:-1].decode('ascii')
     return result