diff --git a/core/admin/migrations/versions/5aeb5811408e_.py b/core/admin/migrations/versions/5aeb5811408e_.py
new file mode 100644
index 00000000..d64cddba
--- /dev/null
+++ b/core/admin/migrations/versions/5aeb5811408e_.py
@@ -0,0 +1,134 @@
+""" Convert all domains and emails to lowercase
+
+Revision ID: 5aeb5811408e
+Revises: cd79ed46d9c2
+Create Date: 2018-12-06 16:07:23.380579
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '5aeb5811408e'
+down_revision = 'f1393877871d'
+
+from alembic import op, config
+import sqlalchemy as sa
+
+
+name_column = lambda: sa.Column('name', sa.String(80), primary_key=True)
+domain_name_column = lambda: sa.Column('domain_name', sa.String(80))
+user_email_column = lambda: sa.Column('user_email', sa.String(255))
+email_columns = lambda: [
+    sa.Column('email', sa.String(255), primary_key=True),
+    sa.Column('localpart', sa.String(80)),
+    domain_name_column()
+]
+id_columns = lambda: [
+    sa.Column('id', sa.Integer(), primary_key=True),
+    user_email_column()
+]
+
+
+domain_table = sa.Table('domain', sa.MetaData(), name_column())
+alternative_table = sa.Table('alternative', sa.MetaData(), name_column(), domain_name_column())
+user_table = sa.Table('user', sa.MetaData(), *email_columns())
+alias_table = sa.Table('alias', sa.MetaData(), *email_columns())
+fetch_table = sa.Table('fetch', sa.MetaData(), *id_columns())
+token_table = sa.Table('token', sa.MetaData(), *id_columns())
+manager_table = sa.Table('manager', sa.MetaData(), domain_name_column(), user_email_column())
+
+
+def upgrade():
+    connection = op.get_bind()
+
+    # drop foreign key constraints
+    with op.batch_alter_table('alias') as batch_op:
+        batch_op.drop_constraint('alias_domain_name_fkey')
+    with op.batch_alter_table('alternative') as batch_op:
+        batch_op.drop_constraint('alternative_domain_name_fkey')
+    with op.batch_alter_table('manager') as batch_op:
+        batch_op.drop_constraint('manager_domain_name_fkey')
+        batch_op.drop_constraint('manager_user_email_fkey')
+    with op.batch_alter_table('token') as batch_op:
+        batch_op.drop_constraint('token_user_email_fkey')
+    with op.batch_alter_table('fetch') as batch_op:
+        batch_op.drop_constraint('fetch_user_email_fkey')
+    with op.batch_alter_table('user') as batch_op:
+        batch_op.drop_constraint('user_domain_name_fkey')
+
+    # lower domain names
+    for domain in connection.execute(domain_table.select()):
+        connection.execute(domain_table.update().where(
+            domain_table.c.name == domain.name
+        ).values(
+            name=domain.name.lower()
+        ))
+    # lower alternatives
+    for alternative in connection.execute(alternative_table.select()):
+        connection.execute(alternative_table.update().where(
+            alternative_table.c.name == alternative.name
+        ).values(
+            name=alternative.name.lower(),
+            domain_name=alternative.domain_name.lower()
+        ))
+    # lower users
+    for user in connection.execute(user_table.select()):
+        connection.execute(user_table.update().where(
+            user_table.c.email == user.email
+        ).values(
+            email=user.email.lower(),
+            localpart=user.localpart.lower(),
+            domain_name=user.domain_name.lower()
+        ))
+    # lower aliases
+    for alias in connection.execute(alias_table.select()):
+        connection.execute(alias_table.update().where(
+            alias_table.c.email == alias.email
+        ).values(
+            email=alias.email.lower(),
+            localpart=alias.localpart.lower(),
+            domain_name=alias.domain_name.lower()
+        ))
+    # lower fetches
+    for fetch in connection.execute(fetch_table.select()):
+        connection.execute(fetch_table.update().where(
+            fetch_table.c.id == fetch.id
+        ).values(
+            user_email=fetch.user_email.lower()
+        ))
+    # lower tokens
+    for token in connection.execute(token_table.select()):
+        connection.execute(token_table.update().where(
+            token_table.c.id == token.id
+        ).values(
+            user_email=token.user_email.lower()
+        ))
+    # lower managers
+    for manager in connection.execute(manager_table.select()):
+        connection.execute(manager_table.update().where(
+            sa.and_(
+                manager_table.c.domain_name == manager.domain_name,
+                manager_table.c.user_email == manager.user_email
+            )
+        ).values(
+            domain_name=manager.domain_name.lower(),
+            user_email=manager.user_email.lower()
+        ))
+
+    # restore foreign key constraints
+    with op.batch_alter_table('alias') as batch_op:
+        batch_op.create_foreign_key('alias_domain_name_fkey', 'domain', ['domain_name'], ['name'])
+    with op.batch_alter_table('user') as batch_op:
+        batch_op.create_foreign_key('user_domain_name_fkey', 'domain', ['domain_name'], ['name'])
+    with op.batch_alter_table('alternative') as batch_op:
+        batch_op.create_foreign_key('alternative_domain_name_fkey', 'domain', ['domain_name'], ['name'])
+    with op.batch_alter_table('manager') as batch_op:
+        batch_op.create_foreign_key('manager_domain_name_fkey', 'domain', ['domain_name'], ['name'])
+        batch_op.create_foreign_key('manager_user_email_fkey', 'user', ['user_email'], ['email'])
+    with op.batch_alter_table('token') as batch_op:
+        batch_op.create_foreign_key('token_user_email_fkey', 'user', ['user_email'], ['email'])
+    with op.batch_alter_table('fetch') as batch_op:
+        batch_op.create_foreign_key('fetch_user_email_fkey', 'user', ['user_email'], ['email'])
+
+
+def downgrade():
+    pass