diff --git a/tempest/lib/common/preprov_creds.py b/tempest/lib/common/preprov_creds.py
index 1011504..ebc435c 100644
--- a/tempest/lib/common/preprov_creds.py
+++ b/tempest/lib/common/preprov_creds.py
@@ -104,10 +104,17 @@
         return hash_dict
 
     @classmethod
+    def _append_project(cls, account, account_hash, hash_dict):
+        key_to_add = account.get('project_name') or account.get('tenant_name')
+        hash_dict['projects'].setdefault(key_to_add, [])
+        hash_dict['projects'][key_to_add].append(account_hash)
+        return hash_dict
+
+    @classmethod
     def get_hash_dict(cls, accounts, admin_role,
                       object_storage_operator_role=None,
                       object_storage_reseller_admin_role=None):
-        hash_dict = {'roles': {}, 'creds': {}, 'networks': {}}
+        hash_dict = {'roles': {}, 'creds': {}, 'networks': {}, 'projects': {}}
 
         # Loop over the accounts read from the yaml file
         for account in accounts:
@@ -163,6 +170,7 @@
                         'Unknown resource type %s, ignoring this field',
                         resource
                     )
+            hash_dict = cls._append_project(account, temp_hash_key, hash_dict)
         return hash_dict
 
     def is_multi_user(self):
@@ -202,6 +210,12 @@
                'the credentials for this allocation request' % ','.join(names))
         raise lib_exc.InvalidCredentials(msg)
 
+    def _exclude_used_projects(self, hashes):
+        excluded_accounts = []
+        for project in [cred.tenant_name for cred in self._creds.values()]:
+            excluded_accounts.extend(self.hash_dict['projects'][project])
+        return hashes - set(excluded_accounts)
+
     def _get_match_hash_list(self, roles=None):
         hashes = []
         if roles:
@@ -222,6 +236,7 @@
             hashes = temp_list
         else:
             hashes = self.hash_dict['creds'].keys()
+        hashes = self._exclude_used_projects(hashes)
         # NOTE(mtreinish): admin is a special case because of the increased
         # privilege set which could potentially cause issues on tests where
         # that is not expected. So unless the admin role isn't specified do