diff --git a/app/models.py b/app/models.py
index bd4a51668..ab8978875 100644
--- a/app/models.py
+++ b/app/models.py
@@ -179,6 +179,26 @@ class ServicePermissionTypes(db.Model):
     name = db.Column(db.String(255), primary_key=True)
 
 
+class AnnualBilling(db.Model):
+    __tablename__ = "annual_billing"
+    id = db.Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4, unique=False)
+    service_id = db.Column(UUID(as_uuid=True), db.ForeignKey('services.id'), unique=False, index=True, nullable=False)
+    financial_year_start = db.Column(db.Integer, nullable=False, default=True, unique=False)
+    free_sms_fragment_limit = db.Column(db.Integer, nullable=False, index=False, unique=False)
+    updated_at = db.Column(db.DateTime, nullable=True, onupdate=datetime.datetime.utcnow)
+    created_at = db.Column(db.DateTime, nullable=False, default=datetime.datetime.utcnow)
+
+    def serialize(self):
+        return {
+            'id': str(self.id),
+            'service_id': str(self.service_id),
+            'free_sms_fragment_limit': str(self.free_sms_fragment_limit),
+            'financial_year_start': str(self.financial_year_start),
+            'created_at': self.created_at.strftime(DATETIME_FORMAT),
+            'updated_at': self.updated_at.strftime(DATETIME_FORMAT) if self.updated_at else None
+        }
+
+
 class Service(db.Model, Versioned):
     __tablename__ = 'services'
 
@@ -213,6 +233,7 @@ class Service(db.Model, Versioned):
     organisation_id = db.Column(UUID(as_uuid=True), db.ForeignKey('organisation.id'), index=True, nullable=True)
     free_sms_fragment_limit = db.Column(db.BigInteger, index=False, unique=False, nullable=True)
     organisation = db.relationship('Organisation')
+    annual_billing = db.relationship('AnnualBilling')
     dvla_organisation_id = db.Column(
         db.String,
         db.ForeignKey('dvla_organisation.id'),
@@ -1462,23 +1483,3 @@ class NotificationEmailReplyTo(db.Model):
         nullable=False,
         primary_key=True
     )
-
-
-class AnnualBilling(db.Model):
-    __tablename__ = "annual_billing"
-    id = db.Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
-    service_id = db.Column(UUID(as_uuid=True), db.ForeignKey('services.id'), unique=False, index=True, nullable=False)
-    financial_year_start = db.Column(db.Integer, nullable=False, default=True)
-    free_sms_fragment_limit = db.Column(db.Integer, nullable=False, index=False, unique=False)
-    updated_at = db.Column(db.DateTime, nullable=True, onupdate=datetime.datetime.utcnow)
-    created_at = db.Column(db.DateTime, nullable=False, default=datetime.datetime.utcnow)
-
-    def serialize(self):
-        return {
-            'id': str(self.id),
-            'service_id': str(self.service_id),
-            'free_sms_fragment_limit': str(self.free_sms_fragment_limit),
-            'financial_year_start': str(self.financial_year_start),
-            'created_at': self.created_at.strftime(DATETIME_FORMAT),
-            'updated_at': self.updated_at.strftime(DATETIME_FORMAT) if self.updated_at else None
-        }
diff --git a/migrations/versions/0126_add_annual_billing.py b/migrations/versions/0126_add_annual_billing.py
index 7f6dfe5b2..1a20a1c0b 100644
--- a/migrations/versions/0126_add_annual_billing.py
+++ b/migrations/versions/0126_add_annual_billing.py
@@ -2,7 +2,7 @@
 
 Revision ID: 0126_add_annual_billing
 Revises: 0125_add_organisation_type
-Create Date: 2017-10-18 11:42:54.261575
+Create Date: 2017-10-19 11:38:32.849573
 
 """
 from alembic import op
@@ -19,11 +19,15 @@ def upgrade():
     sa.Column('service_id', postgresql.UUID(as_uuid=True), nullable=False),
     sa.Column('financial_year_start', sa.Integer(), nullable=False),
     sa.Column('free_sms_fragment_limit', sa.Integer(), nullable=False),
-    sa.Column('created_at', sa.DateTime(), nullable=True),
     sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.Column('created_at', sa.DateTime(), nullable=False),
     sa.ForeignKeyConstraint(['service_id'], ['services.id'], ),
-    sa.PrimaryKeyConstraint('id'))
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_annual_billing_service_id'), 'annual_billing', ['service_id'], unique=False)
 
 
 def downgrade():
+    op.drop_index(op.f('ix_annual_billing_service_id'), table_name='annual_billing')
     op.drop_table('annual_billing')
+