diff --git a/synapse/rest/client/v2_alpha/account.py b/synapse/rest/client/v2_alpha/account.py
index 4d199bbbb..394e6b380 100644
--- a/synapse/rest/client/v2_alpha/account.py
+++ b/synapse/rest/client/v2_alpha/account.py
@@ -130,7 +130,7 @@ class ThreepidRestServlet(RestServlet):
                 400, "Failed to auth 3pid", Codes.THREEPID_AUTH_FAILED
             )
 
-        for reqd in ['medium', 'address', 'validatedAt']:
+        for reqd in ['medium', 'address', 'validated_at']:
             if reqd not in threepid:
                 logger.warn("Couldn't add 3pid: invalid response from ID sevrer")
                 raise SynapseError(500, "Invalid response from ID Server")
@@ -139,7 +139,7 @@ class ThreepidRestServlet(RestServlet):
             auth_user.to_string(),
             threepid['medium'],
             threepid['address'],
-            threepid['validatedAt'],
+            threepid['validated_at'],
         )
 
         if 'bind' in body and body['bind']:
diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py
index dd176c7e7..3640fb4a2 100644
--- a/synapse/rest/client/v2_alpha/register.py
+++ b/synapse/rest/client/v2_alpha/register.py
@@ -121,7 +121,7 @@ class RegisterRestServlet(RestServlet):
         if LoginType.EMAIL_IDENTITY in result:
             threepid = result[LoginType.EMAIL_IDENTITY]
 
-            for reqd in ['medium', 'address', 'validatedAt']:
+            for reqd in ['medium', 'address', 'validated_at']:
                 if reqd not in threepid:
                     logger.info("Can't add incomplete 3pid")
                 else:
@@ -129,7 +129,7 @@ class RegisterRestServlet(RestServlet):
                         user_id,
                         threepid['medium'],
                         threepid['address'],
-                        threepid['validatedAt'],
+                        threepid['validated_at'],
                     )
 
             if 'bind_email' in params and params['bind_email']: